/usr/share/doc/blt-dev/html/graph.html is in blt-dev 2.5.3+dfsg-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434 1435 1436 1437 1438 1439 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483 1484 1485 1486 1487 1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515 1516 1517 1518 1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531 1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573 1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638 1639 1640 1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654 1655 1656 1657 1658 1659 1660 1661 1662 1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712 1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727 1728 1729 1730 1731 1732 1733 1734 1735 1736 1737 1738 1739 1740 1741 1742 1743 1744 1745 1746 1747 1748 1749 1750 1751 1752 1753 1754 1755 1756 1757 1758 1759 1760 1761 1762 1763 1764 1765 1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803 1804 1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820 1821 1822 1823 1824 1825 1826 1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846 1847 1848 1849 1850 1851 1852 1853 1854 1855 1856 1857 1858 1859 1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870 1871 1872 1873 1874 1875 1876 1877 1878 1879 1880 1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910 1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929 1930 1931 1932 1933 1934 1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945 1946 1947 1948 1949 1950 1951 1952 1953 1954 1955 1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 2096 2097 2098 2099 2100 2101 2102 2103 2104 2105 2106 2107 2108 2109 2110 2111 2112 2113 2114 2115 2116 2117 2118 2119 2120 2121 2122 2123 2124 2125 2126 2127 2128 2129 2130 2131 2132 2133 2134 2135 2136 2137 2138 2139 2140 2141 2142 2143 2144 2145 2146 2147 2148 2149 2150 2151 2152 2153 2154 2155 2156 2157 2158 2159 2160 2161 2162 2163 2164 2165 2166 2167 2168 2169 2170 2171 2172 2173 2174 2175 2176 2177 2178 2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 2199 2200 2201 2202 2203 2204 2205 2206 2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 2218 2219 2220 2221 2222 2223 2224 2225 2226 2227 2228 2229 2230 2231 2232 2233 2234 2235 2236 2237 2238 2239 2240 2241 2242 2243 2244 2245 2246 2247 2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260 2261 2262 2263 2264 2265 2266 2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 2281 2282 2283 2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294 2295 2296 2297 2298 2299 2300 2301 2302 2303 2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315 2316 2317 2318 2319 2320 2321 2322 2323 2324 2325 2326 2327 2328 2329 2330 2331 2332 2333 2334 2335 2336 2337 2338 2339 2340 2341 2342 2343 2344 2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360 2361 2362 2363 2364 2365 2366 2367 2368 2369 2370 2371 2372 2373 2374 2375 2376 2377 2378 2379 2380 2381 2382 2383 2384 2385 2386 2387 2388 2389 2390 2391 2392 2393 2394 2395 2396 2397 |
<!-- manual page source format generated by PolyglotMan v3.0.9, -->
<!-- available via anonymous ftp from ftp.cs.berkeley.edu:/ucb/people/phelps/tcltk/rman.tar.Z -->
<HTML>
<HEAD>
<TITLE>graph(n) manual page</TITLE><!--#include virtual="/man/maninc.html"-->
</HEAD>
<BODY bgcolor=white>
<A HREF="#toc">Table of Contents</A><P>
<H2><A NAME="sect0" HREF="#toc0">Name</A></H2>
graph - 2D graph for plotting
X-Y coordinate data.
<H2><A NAME="sect1" HREF="#toc1">Synopsis</A></H2>
<B>graph<I> <I>pathName </I></I></B>?<I>option value</I>?...
<H2><A NAME="sect2" HREF="#toc2">Description</A></H2>
The
<B>graph</B> command creates a graph for plotting two-dimensional data (X-Y coordinates).
It has many configurable components: coordinate axes, elements, legend,
grid lines, cross hairs, etc. They allow you to customize the look and
feel of the graph.
<H2><A NAME="sect3" HREF="#toc3">Introduction</A></H2>
The <B>graph</B> command creates a new window for
plotting two-dimensional data (X-Y coordinates). Data points are plotted
in a rectangular area displayed in the center of the new window. This is
the <I>plotting area</I>. The coordinate axes are drawn in the margins around
the plotting area. By default, the legend is displayed in the right margin.
The title is displayed in top margin. <P>
The <B>graph</B> widget is composed of several
components: coordinate axes, data elements, legend, grid, cross hairs,
pens, postscript, and annotation markers.
<DL>
<DT>axis </DT>
<DD>The graph has four standard
axes (x, x2, y, and y2), but you can create and display any number
of axes. Axes control what region of data is displayed and how the data
is scaled. Each axis consists of the axis line, title, major and minor ticks,
and tick labels. Tick labels display the value at each major tick. </DD>
<DT>crosshairs
</DT>
<DD>Cross hairs are used to position the mouse pointer relative to the X and
Y coordinate axes. Two perpendicular lines, intersecting at the current
location of the mouse, extend across the plotting area to the coordinate
axes. </DD>
<DT>element </DT>
<DD>An element represents a set of data points. Elements can
be plotted with a symbol at each data point and lines connecting the points.
The appearance of the element, such as its symbol, line width, and color
is configurable. </DD>
<DT>grid </DT>
<DD>Extends the major and minor ticks of the X-axis and/or
Y-axis across the plotting area. </DD>
<DT>legend </DT>
<DD>The legend displays the name
and symbol of each data element. The legend can be drawn in any margin
or in the plotting area. </DD>
<DT>marker </DT>
<DD>Markers are used annotate or highlight
areas of the graph. For example, you could use a polygon marker to fill
an area under a curve, or a text marker to label a particular data point.
Markers come in various forms: text strings, bitmaps, connected line
segments, images, polygons, or embedded widgets. </DD>
<DT>pen </DT>
<DD>Pens define attributes
(both symbol and line style) for elements. Data elements use pens to specify
how they should be drawn. A data element may use many pens at once. Here,
the particular pen used for a data point is determined from each element's
weight vector (see the element's <B>-weight</B> and <B>-style</B> options). </DD>
<DT>postscript
</DT>
<DD>The widget can generate encapsulated PostScript output. This component has
several options to configure how the PostScript is generated. </DD>
</DL>
<H2><A NAME="sect4" HREF="#toc4">Syntax</A></H2>
<BR>
<P>
<CODE><B>graph <I>pathName </I></B>?<I>option value</I>?...<BR>
</CODE>The <B>graph</B> command creates a new window <I>pathName</I> and makes it into a <B>graph</B>
widget. At the time this command is invoked, there must not exist a window
named <I>pathName</I>, but <I>pathName</I>'s parent must exist. Additional options may
be specified on the command line or in the option database to configure
aspects of the graph such as its colors and font. See the <B>configure</B> operation
below for the exact details about what <I>option</I> and <I>value</I> pairs are valid.
<P>
If successful, <B>graph</B> returns the path name of the widget. It also creates
a new Tcl command by the same name. You can use this command to invoke
various operations that query or modify the graph. The general form is:
<BR>
<P>
<CODE><I>pathName <I>operation</I></I> ?<I>arg</I>?...<BR>
</CODE>Both <I>operation</I> and its arguments determine the exact behavior of the command.
The operations available for the graph are described in the <FONT SIZE=-1><B>GRAPH OPERATIONS</B></FONT>
section. <P>
The command can also be used to access components of the graph.
<BR>
<P>
<CODE><I>pathName component operation</I> ?<I>arg</I>?...<BR>
</CODE>The operation, now located after the name of the component, is the function
to be performed on that component. Each component has its own set of operations
that manipulate that component. They will be described below in their own
sections.
<H2><A NAME="sect5" HREF="#toc5">Example</A></H2>
The <B>graph</B> command creates a new graph. <BR>
<CODE># Create a new graph. Plotting area is black.<BR>
graph .g -plotbackground black<BR>
</CODE>A new Tcl command .g is also created. This command can be used to query
and modify the graph. For example, to change the title of the graph to
"My Plot", you use the new command and the graph's <B>configure</B> operation. <BR>
<CODE># Change the title.<BR>
.g configure -title "My Plot"<BR>
</CODE>A graph has several components. To access a particular component you use
the component's name. For example, to add data elements, you use the new
command and the <B>element</B> component. <BR>
<CODE># Create a new element named "line1"<BR>
.g element create line1 \<BR>
<tt> </tt> <tt> </tt> -xdata { 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 } \<BR>
<tt> </tt> <tt> </tt> -ydata { 26.18 50.46 72.85 93.31 111.86 128.47 143.14 <BR>
<tt> </tt> <tt> </tt> <tt> </tt> <tt> </tt> 155.85 166.60 175.38 }<BR>
</CODE>The element's X-Y coordinates are specified using lists of numbers. Alternately,
BLT vectors could be used to hold the X-Y coordinates. <BR>
<CODE># Create two vectors and add them to the graph.<BR>
vector xVec yVec<BR>
xVec set { 0.2 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 }<BR>
yVec set { 26.18 50.46 72.85 93.31 111.86 128.47 143.14 155.85 <BR>
<tt> </tt> <tt> </tt> 166.60 175.38 }<BR>
.g element create line1 -xdata xVec -ydata yVec<BR>
</CODE>The advantage of using vectors is that when you modify one, the graph is
automatically redrawn to reflect the new values. <BR>
<CODE># Change the y coordinate of the first point.<BR>
set yVector(0) 25.18<BR>
</CODE>An element named e1 is now created in .b. It is automatically added
to the display list of elements. You can use this list to control in what
order elements are displayed. To query or reset the element display list,
you use the element's <B>show</B> operation. <BR>
<CODE># Get the current display list <BR>
set elemList [.b element show]<BR>
# Remove the first element so it won't be displayed.<BR>
.b element show [lrange $elemList 0 end]<BR>
</CODE>The element will be displayed by as many bars as there are data points
(in this case there are ten). The bars will be drawn centered at the x-coordinate
of the data point. All the bars will have the same attributes (colors,
stipple, etc). The width of each bar is by default one unit. You can change
this with using the <B>-barwidth</B> option. <BR>
<CODE># Change the X-Y coordinates of the first point.<BR>
set xVec(0) 0.18<BR>
set yVec(0) 25.18<BR>
</CODE>An element named line1 is now created in .g. By default, the element's
label in the legend will be also line1. You can change the label, or specify
no legend entry, again using the element's <B>configure</B> operation. <BR>
<CODE># Don't display "line1" in the legend.<BR>
.g element configure line1 -label ""<BR>
</CODE>You can configure more than just the element's label. An element has many
attributes such as symbol type and size, dashed or solid lines, colors,
line width, etc. <BR>
<CODE>.g element configure line1 -symbol square -color red \<BR>
<tt> </tt> <tt> </tt> -dashes { 2 4 2 } -linewidth 2 -pixels 2c<BR>
</CODE>Four coordinate axes are automatically created: x, x2, y, and y2.
And by default, elements are mapped onto the axes x and y. This can
be changed with the <B>-mapx</B> and <B>-mapy</B> options. <BR>
<CODE># Map "line1" on the alternate Y-axis "y2".<BR>
.g element configure line1 -mapy y2<BR>
</CODE>Axes can be configured in many ways too. For example, you change the scale
of the Y-axis from linear to log using the <B>axis</B> component. <BR>
<CODE># Y-axis is log scale.<BR>
.g axis configure y -logscale yes<BR>
</CODE>One important way axes are used is to zoom in on a particular data region.
Zooming is done by simply specifying new axis limits using the <B>-min</B> and
<B>-max</B> configuration options. <BR>
<CODE>.g axis configure x -min 1.0 -max 1.5<BR>
.g axis configure y -min 12.0 -max 55.15<BR>
</CODE>To zoom interactively, you link the <B>axis configure</B> operations with some
user interaction (such as pressing the mouse button), using the <B>bind</B> command.
To convert between screen and graph coordinates, use the <B>invtransform</B>
operation. <BR>
<CODE># Click the button to set a new minimum <BR>
bind .g <ButtonPress-1> { <BR>
%W axis configure x -min [%W axis invtransform x %x]<BR>
%W axis configure x -min [%W axis invtransform x %y]<BR>
}<BR>
</CODE>By default, the limits of the axis are determined from data values. To reset
back to the default limits, set the <B>-min</B> and <B>-max</B> options to the empty value.
<BR>
<CODE># Reset the axes to autoscale again.<BR>
.g axis configure x -min {} -max {}<BR>
.g axis configure y -min {} -max {}<BR>
</CODE>By default, the legend is drawn in the right margin. You can change this
or any legend configuration options using the <B>legend</B> component. <BR>
<CODE># Configure the legend font, color, and relief<BR>
.g legend configure -position left -relief raised \<BR>
<tt> </tt> <tt> </tt> -font fixed -fg blue<BR>
</CODE>To prevent the legend from being displayed, turn on the <B>-hide</B> option. <BR>
<CODE># Don't display the legend.<BR>
.g legend configure -hide yes<BR>
</CODE>The <B>graph</B> widget has simple drawing procedures called markers. They can
be used to highlight or annotate data in the graph. The types of markers
available are bitmaps, images, polygons, lines, or windows. Markers can
be used, for example, to mark or brush points. In this example, is a text
marker that labels the data first point. Markers are created using the
<B>marker</B> component. <BR>
<CODE># Create a label for the first data point of "line1".<BR>
.g marker create text -name first_marker -coords { 0.2 26.18 } \<BR>
<tt> </tt> <tt> </tt> -text "start" -anchor se -xoffset -10 -yoffset -10<BR>
</CODE>This creates a text marker named first_marker. It will display the text
"start" near the coordinates of the first data point. The <B>-anchor</B>, <B>-xoffset</B>,
and <B>-yoffset</B> options are used to display the marker above and to the left
of the data point, so that the data point isn't covered by the marker. By
default, markers are drawn last, on top of data. You can change this with
the <B>-under</B> option. <BR>
<CODE># Draw the label before elements are drawn.<BR>
.g marker configure first_marker -under yes<BR>
</CODE>You can add cross hairs or grid lines using the <B>crosshairs</B> and <B>grid</B> components.
<BR>
<CODE># Display both cross hairs and grid lines.<BR>
.g crosshairs configure -hide no -color red<BR>
.g grid configure -hide no -dashes { 2 2 }<BR>
# Set up a binding to reposition the crosshairs.<BR>
bind .g <Motion> {<BR>
.g crosshairs configure -position @%x,%y<BR>
}<BR>
</CODE>The crosshairs are repositioned as the mouse pointer is moved in the graph.
The pointer X-Y coordinates define the center of the crosshairs. <P>
Finally,
to get hardcopy of the graph, use the <B>postscript</B> component. <BR>
<CODE># Print the graph into file "file.ps"<BR>
.g postscript output file.ps -maxpect yes -decorations no<BR>
</CODE>This generates a file file.ps containing the encapsulated PostScript of
the graph. The option <B>-maxpect</B> says to scale the plot to the size of the
page. Turning off the <B>-decorations</B> option denotes that no borders or color
backgrounds should be drawn (i.e. the background of the margins, legend,
and plotting area will be white).
<H2><A NAME="sect6" HREF="#toc6">Graph Operations</A></H2>
<DL>
<DT><I>pathName <B>axis <I>operation
</I></B></I>?<I>arg</I>?... </DT>
<DD>See the <FONT SIZE=-1><B>AXIS COMPONENTS</B></FONT>
section. </DD>
<DT><I>pathName <B>bar <I>elemName </I></B></I>?<I>option value</I>?...
</DT>
<DD>Creates a new barchart element <I>elemName</I>. It's an error if an element <I>elemName</I>
already exists. See the manual for <B>barchart</B> for details about what <I>option</I>
and <I>value</I> pairs are valid. </DD>
<DT><I>pathName <B>cget</B></I> <I>option</I> </DT>
<DD>Returns the current value
of the configuration option given by <I>option</I>. <I>Option</I> may be any option described
below for the <B>configure</B> operation. </DD>
<DT><I>pathName <B>configure </B></I>?<I>option value</I>?... </DT>
<DD>Queries
or modifies the configuration options of the graph. If <I>option</I> isn't specified,
a list describing the current options for <I>pathName</I> is returned. If <I>option</I>
is specified, but not <I>value</I>, then a list describing <I>option</I> is returned.
If one or more <I>option</I> and <I>value</I> pairs are specified, then for each pair,
the option <I>option</I> is set to <I>value</I>. The following options are valid. <blockquote></DD>
<DT><B>-aspect
<I>width/height</I></B> </DT>
<DD>Force a fixed aspect ratio of <I>width/height</I>, a floating point
number. </DD>
<DT><B>-background <I>color</I></B> </DT>
<DD>Sets the background color. This includes the margins
and legend, but not the plotting area. </DD>
<DT><B>-borderwidth <I>pixels</I></B> </DT>
<DD>Sets the width
of the 3-D border around the outside edge of the widget. The <B>-relief</B> option
determines if the border is to be drawn. The default is 2. </DD>
<DT><B>-bottommargin
<I>pixels</I></B> </DT>
<DD>If non-zero, overrides the computed size of the margin extending
below the X-coordinate axis. If <I>pixels</I> is 0, the automatically computed
size is used. The default is 0. </DD>
<DT><B>-bufferelements <I>boolean</I></B> </DT>
<DD>Indicates whether
an internal pixmap to buffer the display of data elements should be used.
If <I>boolean</I> is true, data elements are drawn to an internal pixmap. This
option is especially useful when the graph is redrawn frequently while
the remains data unchanged (for example, moving a marker across the plot).
See the <FONT SIZE=-1><B>SPEED TIPS</B></FONT>
section. The default is 1. </DD>
<DT><B>-cursor <I>cursor</I></B> </DT>
<DD>Specifies
the widget's cursor. The default cursor is crosshair. </DD>
<DT><B>-font <I>fontName</I></B> </DT>
<DD>Specifies
the font of the graph title. The default is *-Helvetica-Bold-R-Normal-*-18-180-*.
</DD>
<DT><B>-halo <I>pixels</I></B> </DT>
<DD>Specifies a maximum distance to consider when searching for
the closest data point (see the element's <B>closest</B> operation below). Data
points further than <I>pixels</I> away are ignored. The default is 0.5i. </DD>
<DT><B>-height
<I>pixels</I></B> </DT>
<DD>Specifies the requested height of widget. The default is 4i. </DD>
<DT><B>-invertxy
<I>boolean</I></B> </DT>
<DD>Indicates whether the placement X-axis and Y-axis should be inverted.
If <I>boolean</I> is true, the X and Y axes are swapped. The default is 0. </DD>
<DT><B>-justify
<I>justify</I></B> </DT>
<DD>Specifies how the title should be justified. This matters only
when the title contains more than one line of text. <I>Justify</I> must be left,
right, or center. The default is center. </DD>
<DT><B>-leftmargin <I>pixels</I></B> </DT>
<DD>If non-zero,
overrides the computed size of the margin extending from the left edge
of the window to the Y-coordinate axis. If <I>pixels</I> is 0, the automatically
computed size is used. The default is 0. </DD>
<DT><B>-plotbackground <I>color</I></B> </DT>
<DD>Specifies
the background color of the plotting area. The default is white. </DD>
<DT><B>-plotborderwidth
<I>pixels</I></B> </DT>
<DD>Sets the width of the 3-D border around the plotting area. The <B>-plotrelief</B>
option determines if a border is drawn. The default is 2. </DD>
<DT><B>-plotpadx <I>pad</I></B>
</DT>
<DD>Sets the amount of padding to be added to the left and right sides of the
plotting area. <I>Pad</I> can be a list of one or two screen distances. If <I>pad</I>
has two elements, the left side of the plotting area entry is padded by
the first distance and the right side by the second. If <I>pad</I> is just one
distance, both the left and right sides are padded evenly. The default
is 8. </DD>
<DT><B>-plotpady <I>pad</I></B> </DT>
<DD>Sets the amount of padding to be added to the top and
bottom of the plotting area. <I>Pad</I> can be a list of one or two screen distances.
If <I>pad</I> has two elements, the top of the plotting area is padded by the
first distance and the bottom by the second. If <I>pad</I> is just one distance,
both the top and bottom are padded evenly. The default is 8. </DD>
<DT><B>-plotrelief
<I>relief</I></B> </DT>
<DD>Specifies the 3-D effect for the plotting area. <I>Relief</I> specifies
how the interior of the plotting area should appear relative to rest of
the graph; for example, raised means the plot should appear to protrude
from the graph, relative to the surface of the graph. The default is sunken.
</DD>
<DT><B>-relief <I>relief</I></B> </DT>
<DD>Specifies the 3-D effect for the graph widget. <I>Relief</I> specifies
how the graph should appear relative to widget it is packed into; for example,
raised means the graph should appear to protrude. The default is flat.
</DD>
<DT><B>-rightmargin <I>pixels</I></B> </DT>
<DD>If non-zero, overrides the computed size of the margin
extending from the plotting area to the right edge of the window. By default,
the legend is drawn in this margin. If <I>pixels</I> is 0, the automatically
computed size is used. The default is 0. </DD>
<DT><B>-takefocus</B> <I>focus</I> </DT>
<DD>Provides information
used when moving the focus from window to window via keyboard traversal
(e.g., Tab and Shift-Tab). If <I>focus</I> is 0, this means that this window should
be skipped entirely during keyboard traversal. 1 means that the this
window should always receive the input focus. An empty value means that
the traversal scripts make the decision whether to focus on the window.
The default is "". </DD>
<DT><B>-tile <I>image</I></B> </DT>
<DD>Specifies a tiled background for the widget.
If <I>image</I> isn't "", the background is tiled using <I>image</I>. Otherwise, the
normal background color is drawn (see the <B>-background</B> option). <I>Image</I> must
be an image created using the Tk <B>image</B> command. The default is "". </DD>
<DT><B>-title
<I>text</I></B> </DT>
<DD>Sets the title to <I>text</I>. If <I>text</I> is "", no title will be displayed.
</DD>
<DT><B>-topmargin <I>pixels</I></B> </DT>
<DD>If non-zero, overrides the computed size of the margin
above the x2 axis. If <I>pixels</I> is 0, the automatically computed size is
used. The default is 0. </DD>
<DT><B>-width <I>pixels</I></B> </DT>
<DD>Specifies the requested width of
the widget. The default is 5i. </DD>
</DL>
</blockquote>
<DL>
<DT><I>pathName <B>crosshairs <I>operation </I></B></I>?<I>arg</I>? </DT>
<DD>See
the <FONT SIZE=-1><B>CROSSHAIRS COMPONENT</B></FONT>
section. </DD>
<DT><I>pathName <B>element <I>operation </I></B></I>?<I>arg</I>?... </DT>
<DD>See
the <FONT SIZE=-1><B>ELEMENT COMPONENTS</B></FONT>
section. </DD>
<DT><I>pathName <B>extents <I>item</I></B></I> </DT>
<DD>Returns the size
of a particular item in the graph. <I>Item</I> must be either leftmargin, rightmargin,
topmargin, bottommargin, plotwidth, or plotheight. </DD>
<DT><I>pathName <B>grid
<I>operation </I></B></I>?<I>arg</I>?... </DT>
<DD>See the <FONT SIZE=-1><B>GRID COMPONENT</B></FONT>
section. </DD>
<DT><I>pathName <B>invtransform
<I>winX winY</I></B></I> </DT>
<DD>Performs an inverse coordinate transformation, mapping window
coordinates back to graph coordinates, using the standard X-axis and Y-axis.
Returns a list of containing the X-Y graph coordinates. </DD>
<DT><I>pathName <B>inside <I>x
y</I></B></I> </DT>
<DD>Returns 1 is the designated screen coordinate (<I>x</I> and <I>y</I>) is inside the
plotting area and 0 otherwise. </DD>
<DT><I>pathName <B>legend <I>operation </I></B></I>?<I>arg</I>?... </DT>
<DD>See the
<FONT SIZE=-1><B>LEGEND COMPONENT</B></FONT>
section. </DD>
<DT><I>pathName <B>line<B> operation arg</B></B></I>... </DT>
<DD>The operation is
the same as <B>element</B>. </DD>
<DT><I>pathName <B>marker <I>operation </I></B></I>?<I>arg</I>?... </DT>
<DD>See the <FONT SIZE=-1><B>MARKER COMPONENTS</B></FONT>
section. </DD>
<DT><I>pathName <B>postscript <I>operation </I></B></I>?<I>arg</I>?... </DT>
<DD>See the <FONT SIZE=-1><B>POSTSCRIPT COMPONENT</B></FONT>
section. </DD>
<DT><I>pathName <B>snap </B></I>?<I>switches</I>? <I>outputName</I> </DT>
<DD>Takes a snapshot of the graph,
saving the output in <I>outputName</I>. The following switches are available. <blockquote></DD>
<DT><B>-format</B>
<I>format</I> </DT>
<DD>Specifies how the snapshot is output. <I>Format</I> may be one of the following
listed below. The default is photo. <blockquote></DD>
<DT>photo </DT>
<DD>Saves a Tk photo image. <I>OutputName</I>
represents the name of a Tk photo image that must already have been created.
</DD>
<DT>wmf </DT>
<DD>Saves an Aldus Placeable Metafile. <I>OutputName</I> represents the filename
where the metafile is written. If <I>outputName</I> is CLIPBOARD, then output
is written directly to the Windows clipboard. This format is available
only under Microsoft Windows. </DD>
<DT>emf </DT>
<DD>Saves an Enhanced Metafile. <I>OutputName</I>
represents the filename where the metafile is written. If <I>outputName</I> is
CLIPBOARD, then output is written directly to the Windows clipboard.
This format is available only under Microsoft Windows. </DD>
</DL>
</blockquote>
<DL>
<DT><B>-height</B> <I>size</I> </DT>
<DD>Specifies
the height of the graph. <I>Size</I> is a screen distance. The graph will be redrawn
using this dimension, rather than its current window height. </DD>
<DT><B>-width</B> <I>size</I>
</DT>
<DD>Specifies the width of the graph. <I>Size</I> is a screen distance. The graph will
be redrawn using this dimension, rather than its current window width. </DD>
</DL>
</blockquote>
<DL>
<DT><I>pathName
<B>transform <I>x y</I></B></I> </DT>
<DD>Performs a coordinate transformation, mapping graph coordinates
to window coordinates, using the standard X-axis and Y-axis. Returns a list
containing the X-Y screen coordinates. </DD>
<DT><I>pathName <B>xaxis <I>operation</I></B></I> ?<I>arg</I>?... </DT>
<DD></DD>
<DT><I>pathName
<B>x2axis <I>operation</I></B></I> ?<I>arg</I>?... </DT>
<DD></DD>
<DT><I>pathName <B>yaxis <I>operation</I></B></I> ?<I>arg</I>?... </DT>
<DD></DD>
<DT><I>pathName <B>y2axis
<I>operation</I></B></I> ?<I>arg</I>?... </DT>
<DD>See the <FONT SIZE=-1><B>AXIS COMPONENTS</B></FONT>
section. </DD>
</DL>
<H2><A NAME="sect7" HREF="#toc7">Graph Components</A></H2>
A graph
is composed of several components: coordinate axes, data elements, legend,
grid, cross hairs, postscript, and annotation markers. Instead of one big
set of configuration options and operations, the graph is partitioned,
where each component has its own configuration options and operations that
specifically control that aspect or part of the graph.
<H3><A NAME="sect8" HREF="#toc8">Axis Components</A></H3>
Four
coordinate axes are automatically created: two X-coordinate axes (x and
x2) and two Y-coordinate axes (y, and y2). By default, the axis x
is located in the bottom margin, y in the left margin, x2 in the top
margin, and y2 in the right margin. <P>
An axis consists of the axis line,
title, major and minor ticks, and tick labels. Major ticks are drawn at
uniform intervals along the axis. Each tick is labeled with its coordinate
value. Minor ticks are drawn at uniform intervals within major ticks.
<P>
The range of the axis controls what region of data is plotted. Data points
outside the minimum and maximum limits of the axis are not plotted. By
default, the minimum and maximum limits are determined from the data, but
you can reset either limit. <P>
You can have several axes. To create an axis,
invoke the axis component and its create operation. <BR>
<CODE># Create a new axis called "tempAxis"<BR>
.g axis create tempAxis<BR>
</CODE>You map data elements to an axis using the element's -mapy and -mapx configuration
options. They specify the coordinate axes an element is mapped onto. <BR>
<CODE># Now map the tempAxis data to this axis.<BR>
.g element create "e1" -xdata $x -ydata $y -mapy tempAxis<BR>
</CODE>Any number of axes can be displayed simultaneously. They are drawn in the
margins surrounding the plotting area. The default axes x and y are
drawn in the bottom and left margins. The axes x2 and y2 are drawn in
top and right margins. By default, only x and y are shown. Note that
the axes can have different scales. <P>
To display a different axis or more
than one axis, you invoke one of the following components: <B>xaxis</B>, <B>yaxis</B>,
<B>x2axis</B>, and <B>y2axis</B>. Each component has a <B>use</B> operation that designates
the axis (or axes) to be drawn in that corresponding margin: <B>xaxis</B> in the
bottom, <B>yaxis</B> in the left, <B>x2axis</B> in the top, and <B>y2axis</B> in the right. <BR>
<CODE># Display the axis tempAxis in the left margin.<BR>
.g yaxis use tempAxis<BR>
</CODE>The <B>use</B> operation takes a list of axis names as its last argument. This
is the list of axes to be drawn in this margin. <P>
You can configure axes in
many ways. The axis scale can be linear or logarithmic. The values along
the axis can either monotonically increase or decrease. If you need custom
tick labels, you can specify a Tcl procedure to format the label any way
you wish. You can control how ticks are drawn, by changing the major tick
interval or the number of minor ticks. You can define non-uniform tick intervals,
such as for time-series plots. <P>
<DL>
<DT><I>pathName <B>axis bind <I>tagName</I></B></I> ?<I>sequence</I>? ?<I>command</I>?
</DT>
<DD>Associates <I>command</I> with <I>tagName</I> such that whenever the event sequence
given by <I>sequence</I> occurs for an axis with this tag, <I>command</I> will be invoked.
The syntax is similar to the <B>bind</B> command except that it operates on
graph axes, rather than widgets. See the <B>bind</B> manual entry for complete
details on <I>sequence</I> and the substitutions performed on <I>command</I> before
invoking it. <P>
If all arguments are specified then a new binding is created,
replacing any existing binding for the same <I>sequence</I> and <I>tagName</I>. If the
first character of <I>command</I> is + then <I>command</I> augments an existing binding
rather than replacing it. If no <I>command</I> argument is provided then the command
currently associated with <I>tagName</I> and <I>sequence</I> (it's an error occurs if
there's no such binding) is returned. If both <I>command</I> and <I>sequence</I> are
missing then a list of all the event sequences for which bindings have
been defined for <I>tagName</I>. </DD>
<DT><I>pathName <B>axis <B>cget <I>axisName <I>option</I></I></B></B></I> </DT>
<DD>Returns the
current value of the option given by <I>option</I> for <I>axisName</I>. <I>Option</I> may be
any option described below for the axis <B>configure</B> operation. </DD>
<DT><I>pathName <B>axis
<B>configure <I>axisName </I></B></B></I>?<I>axisName</I>?... ?<I>option value</I>?... </DT>
<DD>Queries or modifies the configuration
options of <I>axisName</I>. Several axes can be changed. If <I>option</I> isn't specified,
a list describing all the current options for <I>axisName</I> is returned. If
<I>option</I> is specified, but not <I>value</I>, then a list describing <I>option</I> is returned.
If one or more <I>option</I> and <I>value</I> pairs are specified, then for each pair,
the axis option <I>option</I> is set to <I>value</I>. The following options are valid
for axes. <blockquote></DD>
<DT><B>-bindtags <I>tagList</I></B> </DT>
<DD>Specifies the binding tags for the axis. <I>TagList</I>
is a list of binding tag names. The tags and their order will determine
how events for axes are handled. Each tag in the list matching the current
event sequence will have its Tcl command executed. Implicitly the name
of the element is always the first tag in the list. The default value is
all. </DD>
<DT><B>-color <I>color</I></B> </DT>
<DD>Sets the color of the axis and tick labels. The default
is black. </DD>
<DT><B>-command <I>prefix</I></B> </DT>
<DD>Specifies a Tcl command to be invoked when formatting
the axis tick labels. <I>Prefix</I> is a string containing the name of a Tcl proc
and any extra arguments for the procedure. This command is invoked for
each major tick on the axis. Two additional arguments are passed to the
procedure: the pathname of the widget and the current the numeric value
of the tick. The procedure returns the formatted tick label. If "" is
returned, no label will appear next to the tick. You can get the standard
tick labels again by setting <I>prefix</I> to "". The default is "". <P>
Please
note that this procedure is invoked while the graph is redrawn. You may
query configuration options. But do not them, because this can have unexpected
results. </DD>
<DT><B>-descending <I>boolean</I></B> </DT>
<DD>Indicates whether the values along the axis
are monotonically increasing or decreasing. If <I>boolean</I> is true, the axis
values will be decreasing. The default is 0. </DD>
<DT><B>-hide <I>boolean</I></B> </DT>
<DD>Indicates if
the axis is displayed. If <I>boolean</I> is false the axis will be displayed. Any
element mapped to the axis is displayed regardless. The default value is
0. </DD>
<DT><B>-justify <I>justify</I></B> </DT>
<DD>Specifies how the axis title should be justified. This
matters only when the axis title contains more than one line of text. <I>Justify</I>
must be left, right, or center. The default is center. </DD>
<DT><B>-limits <I>formatStr</I></B>
</DT>
<DD>Specifies a printf-like description to format the minimum and maximum limits
of the axis. The limits are displayed at the top/bottom or left/right sides
of the plotting area. <I>FormatStr</I> is a list of one or two format descriptions.
If one description is supplied, both the minimum and maximum limits are
formatted in the same way. If two, the first designates the format for
the minimum limit, the second for the maximum. If "" is given as either
description, then the that limit will not be displayed. The default is
"". </DD>
<DT><B>-linewidth <I>pixels</I></B> </DT>
<DD>Sets the width of the axis and tick lines. The default
is 1 pixel. </DD>
<DT><B>-logscale <I>boolean</I></B> </DT>
<DD>Indicates whether the scale of the axis is
logarithmic or linear. If <I>boolean</I> is true, the axis is logarithmic. The
default scale is linear. </DD>
<DT><B>-loose <I>boolean</I></B> </DT>
<DD>Indicates whether the limits of the
axis should fit the data points tightly, at the outermost data points,
or loosely, at the outer tick intervals. If the axis limit is set with the
-min or -max option, the axes are displayed tightly. If <I>boolean</I> is true, the
axis range is "loose". The default is 0. </DD>
<DT><B>-majorticks <I>majorList</I></B> </DT>
<DD>Specifies
where to display major axis ticks. You can use this option to display ticks
at non-uniform intervals. <I>MajorList</I> is a list of axis coordinates designating
the location of major ticks. No minor ticks are drawn. If <I>majorList</I> is
"", major ticks will be automatically computed. The default is "". </DD>
<DT><B>-max
<I>value</I></B> </DT>
<DD>Sets the maximum limit of <I>axisName</I>. Any data point greater than
<I>value</I> is not displayed. If <I>value</I> is "", the maximum limit is calculated
using the largest data value. The default is "". </DD>
<DT><B>-min <I>value</I></B> </DT>
<DD>Sets the minimum
limit of <I>axisName</I>. Any data point less than <I>value</I> is not displayed. If
<I>value</I> is "", the minimum limit is calculated using the smallest data
value. The default is "". </DD>
<DT><B>-minorticks <I>minorList</I></B> </DT>
<DD>Specifies where to display
minor axis ticks. You can use this option to display minor ticks at non-uniform
intervals. <I>MinorList</I> is a list of real values, ranging from 0.0 to 1.0, designating
the placement of a minor tick. No minor ticks are drawn if the <B>-majortick</B>
option is also set. If <I>minorList</I> is "", minor ticks will be automatically
computed. The default is "". </DD>
<DT><B>-rotate <I>theta</I></B> </DT>
<DD>Specifies the how many degrees
to rotate the axis tick labels. <I>Theta</I> is a real value representing the number
of degrees to rotate the tick labels. The default is 0.0 degrees. </DD>
<DT><B>-scrollcommand
<I>command</I></B> </DT>
<DD>Specify the prefix for a command used to communicate with scrollbars
for this axis, such as <I>.sbar set</I>. </DD>
<DT><B>-scrollmax <I>value</I></B> </DT>
<DD>Sets the maximum limit
of the axis scroll region. If <I>value</I> is "", the maximum limit is calculated
using the largest data value. The default is "". </DD>
<DT><B>-scrollmin <I>value</I></B> </DT>
<DD>Sets
the minimum limit of axis scroll region. If <I>value</I> is "", the minimum
limit is calculated using the smallest data value. The default is "".
</DD>
<DT><B>-showticks <I>boolean</I></B> </DT>
<DD>Indicates whether axis ticks should be drawn. If <I>boolean</I>
is true, ticks are drawn. If false, only the axis line is drawn. The default
is 1. </DD>
<DT><B>-stepsize <I>value</I></B> </DT>
<DD>Specifies the interval between major axis ticks.
If <I>value</I> isn't a valid interval (must be less than the axis range), the
request is ignored and the step size is automatically calculated. </DD>
<DT><B>-subdivisions
<I>number</I></B> </DT>
<DD>Indicates how many minor axis ticks are to be drawn. For example,
if <I>number</I> is two, only one minor tick is drawn. If <I>number</I> is one, no minor
ticks are displayed. The default is 2. </DD>
<DT><B>-tickfont <I>fontName</I></B> </DT>
<DD>Specifies the
font for axis tick labels. The default is *-Courier-Bold-R-Normal-*-100-*. </DD>
<DT><B>-ticklength
<I>pixels</I></B> </DT>
<DD>Sets the length of major and minor ticks (minor ticks are half the
length of major ticks). If <I>pixels</I> is less than zero, the axis will be inverted
with ticks drawn pointing towards the plot. The default is 0.1i. </DD>
<DT><B>-title
<I>text</I></B> </DT>
<DD>Sets the title of the axis. If <I>text</I> is "", no axis title will be
displayed. </DD>
<DT><B>-titlealternate <I>boolean</I></B> </DT>
<DD>Indicates to display the axis title
in its alternate location. Normally the axis title is centered along the
axis. This option places the axis either to the right (horizontal axes)
or above (vertical axes) the axis. The default is 0. </DD>
<DT><B>-titlecolor <I>color</I></B>
</DT>
<DD>Sets the color of the axis title. The default is black. </DD>
<DT><B>-titlefont <I>fontName</I></B>
</DT>
<DD>Specifies the font for axis title. The default is *-Helvetica-Bold-R-Normal-*-14-140-*.
</DD>
</DL>
<P>
Axis configuration options may be also be set by the <B>option</B> command. The
resource class is Axis. The resource names are the names of the axes
(such as x or x2). <BR>
<CODE>option add *Graph.Axis.Color blue<BR>
option add *Graph.x.LogScale true<BR>
option add *Graph.x2.LogScale false<BR>
</blockquote>
<DL>
<DT></CODE><I>pathName <B>axis <B>create <I>axisName </I></B></B></I>?<I>option value</I>?... </DT>
<DD>Creates a new axis by the
name <I>axisName</I>. No axis by the same name can already exist. <I>Option</I> and <I>value</I>
are described in above in the axis <B>configure</B> operation. </DD>
<DT><I>pathName <B>axis <B>delete
</B></B></I>?<I>axisName</I>?... </DT>
<DD>Deletes the named axes. An axis is not really deleted until it
is not longer in use, so it's safe to delete axes mapped to elements. </DD>
<DT><I>pathName
<B>axis invtransform <I>axisName value</I></B></I> </DT>
<DD>Performs the inverse transformation, changing
the screen coordinate <I>value</I> to a graph coordinate, mapping the value mapped
to <I>axisName</I>. Returns the graph coordinate. </DD>
<DT><I>pathName <B>axis limits <I>axisName</I></B></I>
</DT>
<DD>Returns a list of the minimum and maximum limits for <I>axisName</I>. The order
of the list is min max. </DD>
<DT><I>pathName <B>axis names </B></I>?<I>pattern</I>?... </DT>
<DD>Returns a list of
axes matching zero or more patterns. If no <I>pattern</I> argument is give, the
names of all axes are returned. </DD>
<DT><I>pathName <B>axis transform <I>axisName value</I></B></I> </DT>
<DD>Transforms
the coordinate <I>value</I> to a screen coordinate by mapping the it to <I>axisName</I>.
Returns the transformed screen coordinate. </DD>
<DT><I>pathName <B>axis view <I>axisName</I></B></I>
</DT>
<DD>Change the viewable area of this axis. Use as an argument to a scrollbar's
"<I>-command</I>". </DD>
</DL>
<P>
The default axes are x, y, x2, and y2. But you can display
more than four axes simultaneously. You can also swap in a different axis
with <B>use</B> operation of the special axis components: <B>xaxis</B>, <B>x2axis</B>, <B>yaxis</B>,
and <B>y2axis</B>. <BR>
<CODE>.g create axis temp<BR>
.g create axis time<BR>
...<BR>
.g xaxis use temp<BR>
.g yaxis use time<BR>
</CODE>Only the axes specified for use are displayed on the screen. <P>
The <B>xaxis</B>,
<B>x2axis</B>, <B>yaxis</B>, and <B>y2axis</B> components operate on an axis location rather
than a specific axis like the more general <B>axis</B> component does. They implicitly
control the axis that is currently using to that location. By default,
<B>xaxis</B> uses the x axis, <B>yaxis</B> uses y, <B>x2axis</B> uses x2, and <B>y2axis</B> uses
y2. When more than one axis is displayed in a margin, it represents the
first axis displayed. <P>
The following operations are available for axes. They
mirror exactly the operations of the <B>axis</B> component. The <I>axis</I> argument
must be <B>xaxis</B>, <B>x2axis</B>, <B>yaxis</B>, or <B>y2axis</B>. This feature is deprecated since
more than one axis can now be used a margin. You should only use the <B>xaxis</B>,
<B>x2axis</B>, <B>yaxis</B>, and <B>y2axis</B> components with the <B>use</B> operation. For all other
operations, use the general <B>axis</B> component instead.
<DL>
<DT><I>pathName <I>axis <B>cget <I>option</I></B></I></I>
</DT>
<DD></DD>
<DT><I>pathName <I>axis <B>configure </B></I></I>?<I>option value</I>?... </DT>
<DD></DD>
<DT><I>pathName <I>axis<B> invtransform <I>value</I></B></I></I>
</DT>
<DD></DD>
<DT><I>pathName <I>axis <B>limits</B></I></I> </DT>
<DD></DD>
<DT><I>pathName <I>axis<B> transform <I>value</I></B></I></I> </DT>
<DD></DD>
<DT><I>pathName <I>axis<B> use </B></I></I>?<I>axisName</I>?
</DT>
<DD>Designates the axis <I>axisName</I> is to be displayed at this location. <I>AxisName</I>
can not be already in use at another location. This command returns the
name of the axis currently using this location. </DD>
</DL>
<H3><A NAME="sect9" HREF="#toc9">Crosshairs Component</A></H3>
Cross
hairs consist of two intersecting lines (one vertical and one horizontal)
drawn completely across the plotting area. They are used to position the
mouse in relation to the coordinate axes. Cross hairs differ from line
markers in that they are implemented using XOR drawing primitives. This
means that they can be quickly drawn and erased without redrawing the entire
graph. Note that crosshair are enabled by calling <B>Blt_Crosshairs</B> and turned
off by calling <B>Blt_ResetCrosshairs</B>. Similarly call <B>Blt_ZoomStack</B> for zooming.
<P>
The following operations are available for cross hairs:
<DL>
<DT><I>pathName <B>crosshairs
cget <I>option</I></B></I> </DT>
<DD>Returns the current value of the cross hairs configuration
option given by <I>option</I>. <I>Option</I> may be any option described below for the
cross hairs <B>configure</B> operation. </DD>
<DT><I>pathName <B>crosshairs configure </B></I>?<I>option value</I>?...
</DT>
<DD>Queries or modifies the configuration options of the cross hairs. If
<I>option</I> isn't specified, a list describing all the current options for the
cross hairs is returned. If <I>option</I> is specified, but not <I>value</I>, then a
list describing <I>option</I> is returned. If one or more <I>option</I> and <I>value</I> pairs
are specified, then for each pair, the cross hairs option <I>option</I> is set
to <I>value</I>. The following options are available for cross hairs. <blockquote></DD>
<DT><B>-color <I>color</I></B>
</DT>
<DD>Sets the color of the cross hairs. The default is black. </DD>
<DT><B>-dashes <I>dashList</I></B>
</DT>
<DD>Sets the dash style of the cross hairs. <I>DashList</I> is a list of up to 11 numbers
that alternately represent the lengths of the dashes and gaps on the cross
hair lines. Each number must be between 1 and 255. If <I>dashList</I> is "",
the cross hairs will be solid lines. </DD>
<DT><B>-hide <I>boolean</I></B> </DT>
<DD>Indicates whether cross
hairs are drawn. If <I>boolean</I> is true, cross hairs are not drawn. The default
is yes. </DD>
<DT><B>-linewidth <I>pixels</I></B> </DT>
<DD>Set the width of the cross hair lines. The default
is 1. </DD>
<DT><B>-position <I>pos</I></B> </DT>
<DD>Specifies the screen position where the cross hairs
intersect. <I>Pos</I> must be in the form "<I>@x,y</I>", where <I>x</I> and <I>y</I> are the window
coordinates of the intersection. </DD>
</DL>
<P>
Cross hairs configuration options may be
also be set by the <B>option</B> command. The resource name and class are crosshairs
and Crosshairs respectively. <BR>
<CODE>option add *Graph.Crosshairs.LineWidth 2<BR>
option add *Graph.Crosshairs.Color red<BR>
</blockquote>
<DL>
<DT></CODE><I>pathName <B>crosshairs off</B></I> </DT>
<DD>Turns off the cross hairs. </DD>
<DT><I>pathName <B>crosshairs
on</B></I> </DT>
<DD>Turns on the display of the cross hairs. </DD>
<DT><I>pathName <B>crosshairs toggle</B></I>
</DT>
<DD>Toggles the current state of the cross hairs, alternately mapping and unmapping
the cross hairs. </DD>
</DL>
<H3><A NAME="sect10" HREF="#toc10">Element Components</A></H3>
A data element represents a set of data.
It contains x and y vectors containing the coordinates of the data points.
Elements can be displayed with a symbol at each data point and lines connecting
the points. Elements also control the appearance of the data, such as the
symbol type, line width, color etc. <P>
When new data elements are created,
they are automatically added to a list of displayed elements. The display
list controls what elements are drawn and in what order. <P>
The following
operations are available for elements.
<DL>
<DT><I>pathName <B>element activate <I>elemName
</I></B></I>?<I>index</I>?... </DT>
<DD>Specifies the data points of element <I>elemName</I> to be drawn using
active foreground and background colors. <I>ElemName</I> is the name of the element
and <I>index</I> is a number representing the index of the data point. If no indices
are present then all data points become active. </DD>
<DT><I>pathName <B>element bind <I>tagName</I></B></I>
?<I>sequence</I>? ?<I>command</I>? </DT>
<DD>Associates <I>command</I> with <I>tagName</I> such that whenever
the event sequence given by <I>sequence</I> occurs for an element with this tag,
<I>command</I> will be invoked. The syntax is similar to the <B>bind</B> command except
that it operates on graph elements, rather than widgets. See the <B>bind</B> manual
entry for complete details on <I>sequence</I> and the substitutions performed
on <I>command</I> before invoking it. <P>
If all arguments are specified then a
new binding is created, replacing any existing binding for the same <I>sequence</I>
and <I>tagName</I>. If the first character of <I>command</I> is + then <I>command</I> augments
an existing binding rather than replacing it. If no <I>command</I> argument is
provided then the command currently associated with <I>tagName</I> and <I>sequence</I>
(it's an error occurs if there's no such binding) is returned. If both <I>command</I>
and <I>sequence</I> are missing then a list of all the event sequences for which
bindings have been defined for <I>tagName</I>. </DD>
<DT><I>pathName <B>element cget <I>elemName
<I>option</I></I></B></I> </DT>
<DD>Returns the current value of the element configuration option given
by <I>option</I>. <I>Option</I> may be any of the options described below for the element
<B>configure</B> operation. </DD>
<DT><I>pathName <B>element closest <I>x y</I></B></I> <I>varName</I> ?<I>option value</I>?...
?<I>elemName</I>?... </DT>
<DD><P>
Searches for the data point closest to the window coordinates
<I>x</I> and <I>y</I>. By default, all elements are searched. Hidden elements (see the
<B>-hide</B> option is false) are ignored. You can limit the search by specifying
only the elements you want to be considered. <I>ElemName</I> must be the name
of an element that is not be hidden. <I>VarName</I> is the name of a Tcl array
variable and will contain the search results: the name of the closest element,
the index of the closest data point, and the graph coordinates of the point.
Returns 0, if no data point within the threshold distance can be found,
otherwise 1 is returned. The following <I>option</I>-<I>value</I> pairs are available.
<blockquote></DD>
<DT><B>-along <I>direction</I></B> </DT>
<DD>Search for the closest element using the following criteria:
<blockquote></DD>
<DT>x </DT>
<DD>Find closest element vertically from the given X-coordinate. </DD>
<DT>y </DT>
<DD>Find
the closest element horizontally from the given Y-coordinate. </DD>
<DT>both </DT>
<DD>Find
the closest element for the given point (using both the X and Y coordinates).
</DD>
</DL>
</blockquote>
<DL>
<DT><B>-halo <I>pixels</I></B> </DT>
<DD>Specifies a threshold distance where selected data points
are ignored. <I>Pixels</I> is a valid screen distance, such as 2 or 1.2i. If
this option isn't specified, then it defaults to the value of the graph's
<B>-halo</B> option. </DD>
<DT><B>-interpolate <I>string</I></B> </DT>
<DD>Indicates whether to consider projections
that lie along the line segments connecting data points when searching
for the closest point. The default value is 0. The values for <I>string</I> are
described below. <blockquote></DD>
<DT>no </DT>
<DD>Search only for the closest data point. </DD>
<DT>yes </DT>
<DD>Search
includes projections that lie along the line segments connecting the data
points. </DD>
</DL>
</blockquote>
</blockquote>
<DL>
<DT><I>pathName <B>element configure <I>elemName </I></B></I>?<I>elemName</I>... ?<I>option value</I>?... </DT>
<DD>Queries
or modifies the configuration options for elements. Several elements can
be modified at the same time. If <I>option</I> isn't specified, a list describing
all the current options for <I>elemName</I> is returned. If <I>option</I> is specified,
but not <I>value</I>, then a list describing the option <I>option</I> is returned. If
one or more <I>option</I> and <I>value</I> pairs are specified, then for each pair, the
element option <I>option</I> is set to <I>value</I>. The following options are valid
for elements. <blockquote></DD>
<DT><B>-activepen <I>penName</I></B> </DT>
<DD>Specifies pen to use to draw active element.
If <I>penName</I> is "", no active elements will be drawn. The default is
activeLine. </DD>
<DT><B>-bindtags <I>tagList</I></B> </DT>
<DD>Specifies the binding tags for the element.
<I>TagList</I> is a list of binding tag names. The tags and their order will
determine how events are handled for elements. Each tag in the list matching
the current event sequence will have its Tcl command executed. Implicitly
the name of the element is always the first tag in the list. The default
value is all. </DD>
<DT><B>-color <I>color</I></B> </DT>
<DD>Sets the color of the traces connecting the
data points. </DD>
<DT><B>-dashes <I>dashList</I></B> </DT>
<DD>Sets the dash style of element line. <I>DashList</I>
is a list of up to 11 numbers that alternately represent the lengths of
the dashes and gaps on the element line. Each number must be between 1
and 255. If <I>dashList</I> is "", the lines will be solid. </DD>
<DT><B>-data <I>coordList</I></B> </DT>
<DD>Specifies
the X-Y coordinates of the data. <I>CoordList</I> is a list of numeric expressions
representing the X-Y coordinate pairs of each data point. </DD>
<DT><B>-fill <I>color</I></B> </DT>
<DD>Sets
the interior color of symbols. If <I>color</I> is "", then the interior of the
symbol is transparent. If <I>color</I> is defcolor, then the color will be the
same as the <B>-color</B> option. The default is defcolor. </DD>
<DT><B>-hide <I>boolean</I></B> </DT>
<DD>Indicates
whether the element is displayed. The default is no. </DD>
<DT><B>-label <I>text</I></B> </DT>
<DD>Sets
the element's label in the legend. If <I>text</I> is "", the element will have
no entry in the legend. The default label is the element's name. </DD>
<DT><B>-linewidth
<I>pixels</I></B> </DT>
<DD>Sets the width of the connecting lines between data points. If
<I>pixels</I> is 0, no connecting lines will be drawn between symbols. The default
is 0. </DD>
<DT><B>-mapx <I>xAxis</I></B> </DT>
<DD>Selects the X-axis to map the element's X-coordinates onto.
<I>XAxis</I> must be the name of an axis. The default is x. </DD>
<DT><B>-mapy <I>yAxis</I></B> </DT>
<DD>Selects
the Y-axis to map the element's Y-coordinates onto. <I>YAxis</I> must be the name
of an axis. The default is y. </DD>
<DT><B>-offdash <I>color</I></B> </DT>
<DD>Sets the color of the stripes
when traces are dashed (see the <B>-dashes</B> option). If <I>color</I> is "", then
the "off" pixels will represent gaps instead of stripes. If <I>color</I> is defcolor,
then the color will be the same as the <B>-color</B> option. The default is defcolor.
</DD>
<DT><B>-outline <I>color</I></B> </DT>
<DD>Sets the color or the outline around each symbol. If <I>color</I>
is "", then no outline is drawn. If <I>color</I> is defcolor, then the color
will be the same as the <B>-color</B> option. The default is defcolor. </DD>
<DT><B>-pen <I>penname</I></B>
</DT>
<DD>Set the pen to use for this element. </DD>
<DT><B>-outlinewidth <I>pixels</I></B> </DT>
<DD>Sets the width
of the outline bordering each symbol. If <I>pixels</I> is 0, no outline will
be drawn. The default is 1. </DD>
<DT><B>-pixels <I>pixels</I></B> </DT>
<DD>Sets the size of symbols. If
<I>pixels</I> is 0, no symbols will be drawn. The default is 0.125i. </DD>
<DT><B>-scalesymbols
<I>boolean</I></B> </DT>
<DD>If <I>boolean</I> is true, the size of the symbols drawn for <I>elemName</I>
will change with scale of the X-axis and Y-axis. At the time this option is
set, the current ranges of the axes are saved as the normalized scales
(i.e scale factor is 1.0) and the element is drawn at its designated size
(see the <B>-pixels</B> option). As the scale of the axes change, the symbol will
be scaled according to the smaller of the X-axis and Y-axis scales. If <I>boolean</I>
is false, the element's symbols are drawn at the designated size, regardless
of axis scales. The default is 0. </DD>
<DT><B>-smooth <I>smooth</I></B> </DT>
<DD>Specifies how connecting
line segments are drawn between data points. <I>Smooth</I> can be either linear,
step, natural, or quadratic. If <I>smooth</I> is linear, a single line
segment is drawn, connecting both data points. When <I>smooth</I> is step, two
line segments are drawn. The first is a horizontal line segment that steps
the next X-coordinate. The second is a vertical line, moving to the next
Y-coordinate. Both <I>natural</I> and <I>quadratic</I> generate multiple segments between
data points. If <I>natural</I>, the segments are generated using a cubic spline.
If <I>quadratic</I>, a quadratic spline is used. The default is <I>linear</I>. </DD>
<DT><B>-styles
<I>styleList</I></B> </DT>
<DD>Specifies what pen to use based on the range of weights given.
<I>StyleList</I> is a list of style specifications. Each style specification, in
turn, is a list consisting of a pen name, and optionally a minimum and
maximum range. Data points whose weight (see the <B>-weight</B> option) falls in
this range, are drawn with this pen. If no range is specified it defaults
to the index of the pen in the list. Note that this affects only symbol
attributes. Line attributes, such as line width, dashes, etc. are ignored.
</DD>
<DT><B>-symbol <I>symbol</I></B> </DT>
<DD>Specifies the symbol for data points. <I>Symbol</I> can be either
square, circle, diamond, plus, cross, splus, scross, triangle,
"" (where no symbol is drawn), or a bitmap. Bitmaps are specified as
"<I>source</I> ?<I>mask</I>?", where <I>source</I> is the name of the bitmap, and <I>mask</I> is the
bitmap's optional mask. The default is circle. </DD>
<DT><B>-trace <I>direction</I></B> </DT>
<DD>Indicates
whether connecting lines between data points (whose X-coordinate values
are either increasing or decreasing) are drawn. <I>Direction</I> must be increasing,
decreasing, or both. For example, if <I>direction</I> is increasing, connecting
lines will be drawn only between those data points where X-coordinate values
are monotonically increasing. If <I>direction</I> is both, connecting lines
will be draw between all data points. The default is both. </DD>
<DT><B>-weights <I>wVec</I></B>
</DT>
<DD>Specifies the weights of the individual data points. This, with the list
pen styles (see the <B>-styles</B> option), controls how data points are drawn.
<I>WVec</I> is the name of a BLT vector or a list of numeric expressions representing
the weights for each data point. </DD>
<DT><B>-xdata <I>xVec</I></B> </DT>
<DD>Specifies the X-coordinates
of the data. <I>XVec</I> is the name of a BLT vector or a list of numeric expressions.
</DD>
<DT><B>-ydata <I>yVec</I></B> </DT>
<DD>Specifies the Y-coordinates of the data. <I>YVec</I> is the name of
a BLT vector or a list of numeric expressions. </DD>
</DL>
<P>
Element configuration options
may also be set by the <B>option</B> command. The resource class is Element.
The resource name is the name of the element. <BR>
<CODE>option add *Graph.Element.symbol line<BR>
option add *Graph.e1.symbol line<BR>
</blockquote>
<DL>
<DT></CODE><I>pathName <B>element create <I>elemName</I></B></I> ?<I>option value</I>?... </DT>
<DD>Creates a new element <I>elemName</I>.
It's an error is an element <I>elemName</I> already exists. If additional arguments
are present, they specify options valid for the element <B>configure</B> operation.
</DD>
<DT><I>pathName <B>element deactivate <I>elemName</I></B></I> ?<I>elemName</I>?... </DT>
<DD>Deactivates all the elements
matching <I>pattern</I>. Elements whose names match any of the patterns given are
redrawn using their normal colors. </DD>
<DT><I>pathName <B>element delete</B></I> ?<I>elemName</I>?... </DT>
<DD>Deletes
all the named elements. The graph is automatically redrawn. </DD>
<DT><I>pathName <B>element
exists <I>elemName</I></B></I> </DT>
<DD>Returns 1 if an element <I>elemName</I> currently exists and
0 otherwise. </DD>
<DT><I>pathName <B>element names </B></I>?<I>pattern</I>?... </DT>
<DD>Returns the elements matching
one or more pattern. If no <I>pattern</I> is given, the names of all elements
is returned. </DD>
<DT><I>pathName <B>element show</B></I> ?<I>nameList</I>? </DT>
<DD>Queries or modifies the
element display list. The element display list designates the elements
drawn and in what order. <I>NameList</I> is a list of elements to be displayed
in the order they are named. If there is no <I>nameList</I> argument, the current
display list is returned. </DD>
<DT><I>pathName <B>element type</B></I> <I>elemName</I> </DT>
<DD>Returns the type
of <I>elemName</I>. If the element is a bar element, the commands returns the
string "bar", otherwise it returns "line". </DD>
</DL>
<H3><A NAME="sect11" HREF="#toc11"></CODE>Grid Component</A></H3>
Grid lines
extend from the major and minor ticks of each axis horizontally or vertically
across the plotting area. The following operations are available for grid
lines.
<DL>
<DT><I>pathName <B>grid cget <I>option</I></B></I> </DT>
<DD>Returns the current value of the grid line
configuration option given by <I>option</I>. <I>Option</I> may be any option described
below for the grid <B>configure</B> operation. </DD>
<DT><I>pathName <B>grid configure</B></I> ?<I>option
value</I>?... </DT>
<DD>Queries or modifies the configuration options for grid lines. If
<I>option</I> isn't specified, a list describing all the current grid options for
<I>pathName</I> is returned. If <I>option</I> is specified, but not <I>value</I>, then a list
describing <I>option</I> is returned. If one or more <I>option</I> and <I>value</I> pairs are
specified, then for each pair, the grid line option <I>option</I> is set to <I>value</I>.
The following options are valid for grid lines. <blockquote></DD>
<DT><B>-color <I>color</I></B> </DT>
<DD>Sets the color
of the grid lines. The default is black. </DD>
<DT><B>-dashes <I>dashList</I></B> </DT>
<DD>Sets the dash
style of the grid lines. <I>DashList</I> is a list of up to 11 numbers that alternately
represent the lengths of the dashes and gaps on the grid lines. Each number
must be between 1 and 255. If <I>dashList</I> is "", the grid will be solid lines.
</DD>
<DT><B>-hide <I>boolean</I></B> </DT>
<DD>Indicates whether the grid should be drawn. If <I>boolean</I> is true,
grid lines are not shown. The default is yes. </DD>
<DT><B>-linewidth <I>pixels</I></B> </DT>
<DD>Sets the
width of grid lines. The default width is 1. </DD>
<DT><B>-mapx <I>xAxis</I></B> </DT>
<DD>Specifies the
X-axis to display grid lines. <I>XAxis</I> must be the name of an axis or ""
for no grid lines. The default is "". </DD>
<DT><B>-mapy <I>yAxis</I></B> </DT>
<DD>Specifies the Y-axis
to display grid lines. <I>YAxis</I> must be the name of an axis or "" for no
grid lines. The default is y. </DD>
<DT><B>-minor <I>boolean</I></B> </DT>
<DD>Indicates whether the grid
lines should be drawn for minor ticks. If <I>boolean</I> is true, the lines will
appear at minor tick intervals. The default is 1. </DD>
</DL>
<P>
Grid configuration options
may also be set by the <B>option</B> command. The resource name and class are
grid and Grid respectively. <BR>
<CODE>option add *Graph.grid.LineWidth 2<BR>
option add *Graph.Grid.Color black<BR>
<DL>
<DT></CODE><B>-raised <I>boolean</I></B> </DT>
<DD>Grid is to be raised or drawn over elements. </DD>
</DL>
</blockquote>
<DL>
<DT><I>pathName <B>grid
off</B></I> </DT>
<DD>Turns off the display the grid lines. </DD>
<DT><I>pathName <B>grid on</B></I> </DT>
<DD>Turns on the
display the grid lines. </DD>
<DT><I>pathName <B>grid toggle</B></I> </DT>
<DD>Toggles the display of the
grid. </DD>
</DL>
<H3><A NAME="sect12" HREF="#toc12">Legend Component</A></H3>
The legend displays a list of the data elements.
Each entry consists of the element's symbol and label. The legend can appear
in any margin (the default location is in the right margin). It can also
be positioned anywhere within the plotting area. <P>
The following operations
are valid for the legend.
<DL>
<DT><I>pathName <B>legend activate <I>pattern</I></B></I>... </DT>
<DD>Selects legend
entries to be drawn using the active legend colors and relief. All entries
whose element names match <I>pattern</I> are selected. To be selected, the element
name must match only one <I>pattern</I>. </DD>
<DT><I>pathName <B>legend bind <I>tagName</I></B></I> ?<I>sequence</I>?
?<I>command</I>? </DT>
<DD>Associates <I>command</I> with <I>tagName</I> such that whenever the event
sequence given by <I>sequence</I> occurs for a legend entry with this tag, <I>command</I>
will be invoked. Implicitly the element names in the entry are tags. The
syntax is similar to the <B>bind</B> command except that it operates on legend
entries, rather than widgets. See the <B>bind</B> manual entry for complete details
on <I>sequence</I> and the substitutions performed on <I>command</I> before invoking
it. <P>
If all arguments are specified then a new binding is created, replacing
any existing binding for the same <I>sequence</I> and <I>tagName</I>. If the first character
of <I>command</I> is + then <I>command</I> augments an existing binding rather than
replacing it. If no <I>command</I> argument is provided then the command currently
associated with <I>tagName</I> and <I>sequence</I> (it's an error occurs if there's no
such binding) is returned. If both <I>command</I> and <I>sequence</I> are missing then
a list of all the event sequences for which bindings have been defined
for <I>tagName</I>. </DD>
<DT><I>pathName <B>legend cget <I>option</I></B></I> </DT>
<DD>Returns the current value of a
legend configuration option. <I>Option</I> may be any option described below in
the legend <B>configure</B> operation. </DD>
<DT><I>pathName <B>legend configure </B></I>?<I>option value</I>?...
</DT>
<DD>Queries or modifies the configuration options for the legend. If <I>option</I>
isn't specified, a list describing the current legend options for <I>pathName</I>
is returned. If <I>option</I> is specified, but not <I>value</I>, then a list describing
<I>option</I> is returned. If one or more <I>option</I> and <I>value</I> pairs are specified,
then for each pair, the legend option <I>option</I> is set to <I>value</I>. The following
options are valid for the legend. <blockquote></DD>
<DT><B>-activebackground <I>color</I></B> </DT>
<DD>Sets the background
color for active legend entries. All legend entries marked active (see
the legend <B>activate</B> operation) are drawn using this background color. </DD>
<DT><B>-activeborderwidth
<I>pixels</I></B> </DT>
<DD>Sets the width of the 3-D border around the outside edge of the active
legend entries. The default is 2. </DD>
<DT><B>-activeforeground <I>color</I></B> </DT>
<DD>Sets the foreground
color for active legend entries. All legend entries marked as active (see
the legend <B>activate</B> operation) are drawn using this foreground color. </DD>
<DT><B>-activerelief
<I>relief</I></B> </DT>
<DD>Specifies the 3-D effect desired for active legend entries. <I>Relief</I>
denotes how the interior of the entry should appear relative to the legend;
for example, raised means the entry should appear to protrude from the
legend, relative to the surface of the legend. The default is flat. </DD>
<DT><B>-anchor
<I>anchor</I></B> </DT>
<DD>Tells how to position the legend relative to the positioning point
for the legend. This is dependent on the value of the <B>-position</B> option.
The default is center. <blockquote></DD>
<DT>left or right </DT>
<DD>The anchor describes how to position
the legend vertically. </DD>
<DT>top or bottom </DT>
<DD>The anchor describes how to position
the legend horizontally. </DD>
<DT>@x,y </DT>
<DD>The anchor specifies how to position the
legend relative to the positioning point. For example, if <I>anchor</I> is center
then the legend is centered on the point; if <I>anchor</I> is n then the legend
will be drawn such that the top center point of the rectangular region
occupied by the legend will be at the positioning point. </DD>
<DT>plotarea </DT>
<DD>The
anchor specifies how to position the legend relative to the plotting area.
For example, if <I>anchor</I> is center then the legend is centered in the plotting
area; if <I>anchor</I> is ne then the legend will be drawn such that occupies
the upper right corner of the plotting area. </DD>
</DL>
</blockquote>
<DL>
<DT><B>-background <I>color</I></B> </DT>
<DD>Sets the background
color of the legend. If <I>color</I> is "", the legend background with be transparent.
</DD>
<DT><B>-bindtags <I>tagList</I></B> </DT>
<DD>Specifies the binding tags for legend entries. <I>TagList</I>
is a list of binding tag names. The tags and their order will determine
how events are handled for legend entries. Each tag in the list matching
the current event sequence will have its Tcl command executed. The default
value is all. </DD>
<DT><B>-borderwidth <I>pixels</I></B> </DT>
<DD>Sets the width of the 3-D border around
the outside edge of the legend (if such border is being drawn; the <B>relief</B>
option determines this). The default is 2 pixels. </DD>
<DT><B>-font <I>fontName</I></B> </DT>
<DD><I>FontName</I>
specifies a font to use when drawing the labels of each element into the
legend. The default is *-Helvetica-Bold-R-Normal-*-12-120-*. </DD>
<DT><B>-foreground <I>color</I></B>
</DT>
<DD>Sets the foreground color of the text drawn for the element's label. The
default is black. </DD>
<DT><B>-hide <I>boolean</I></B> </DT>
<DD>Indicates whether the legend should be
displayed. If <I>boolean</I> is true, the legend will not be draw. The default
is no. </DD>
<DT><B>-ipadx <I>pad</I></B> </DT>
<DD>Sets the amount of internal padding to be added to the
width of each legend entry. <I>Pad</I> can be a list of one or two screen distances.
If <I>pad</I> has two elements, the left side of the legend entry is padded by
the first distance and the right side by the second. If <I>pad</I> is just one
distance, both the left and right sides are padded evenly. The default
is 2. </DD>
<DT><B>-ipady <I>pad</I></B> </DT>
<DD>Sets an amount of internal padding to be added to the
height of each legend entry. <I>Pad</I> can be a list of one or two screen distances.
If <I>pad</I> has two elements, the top of the entry is padded by the first distance
and the bottom by the second. If <I>pad</I> is just one distance, both the top
and bottom of the entry are padded evenly. The default is 2. </DD>
<DT><B>-padx <I>pad</I></B> </DT>
<DD>Sets
the padding to the left and right exteriors of the legend. <I>Pad</I> can be a
list of one or two screen distances. If <I>pad</I> has two elements, the left
side of the legend is padded by the first distance and the right side by
the second. If <I>pad</I> has just one distance, both the left and right sides
are padded evenly. The default is 4. </DD>
<DT><B>-pady <I>pad</I></B> </DT>
<DD>Sets the padding above and
below the legend. <I>Pad</I> can be a list of one or two screen distances. If
<I>pad</I> has two elements, the area above the legend is padded by the first
distance and the area below by the second. If <I>pad</I> is just one distance,
both the top and bottom areas are padded evenly. The default is 0. </DD>
<DT><B>-position
<I>pos</I></B> </DT>
<DD>Specifies where the legend is drawn. The <B>-anchor</B> option also affects
where the legend is positioned. If <I>pos</I> is left, left, top, or bottom,
the legend is drawn in the specified margin. If <I>pos</I> is plotarea, then
the legend is drawn inside the plotting area at a particular anchor. If
<I>pos</I> is in the form "<I>@x,y</I>", where <I>x</I> and <I>y</I> are the window coordinates, the
legend is drawn in the plotting area at the specified coordinates. The
default is right. </DD>
<DT><B>-raised <I>boolean</I></B> </DT>
<DD>Indicates whether the legend is above
or below the data elements. This matters only if the legend is in the plotting
area. If <I>boolean</I> is true, the legend will be drawn on top of any elements
that may overlap it. The default is no. </DD>
<DT><B>-relief <I>relief</I></B> </DT>
<DD>Specifies the 3-D
effect for the border around the legend. <I>Relief</I> specifies how the interior
of the legend should appear relative to the graph; for example, raised
means the legend should appear to protrude from the graph, relative to
the surface of the graph. The default is sunken. </DD>
</DL>
<P>
Legend configuration
options may also be set by the <B>option</B> command. The resource name and class
are legend and Legend respectively. <BR>
<CODE>option add *Graph.legend.Foreground blue<BR>
option add *Graph.Legend.Relief raised<BR>
</blockquote>
<DL>
<DT></CODE><I>pathName <B>legend deactivate <I>pattern</I></B></I>... </DT>
<DD>Selects legend entries to be drawn using
the normal legend colors and relief. All entries whose element names match
<I>pattern</I> are selected. To be selected, the element name must match only
one <I>pattern</I>. </DD>
<DT><I>pathName <B>legend get <I>pos</I></B></I> </DT>
<DD>Returns the name of the element whose
entry is at the screen position <I>pos</I> in the legend. <I>Pos</I> must be in the form
"<I>@x,y</I>", where <I>x</I> and <I>y</I> are window coordinates. If the given coordinates
do not lie over a legend entry, "" is returned. </DD>
</DL>
<H3><A NAME="sect13" HREF="#toc13">Pen Components</A></H3>
Pens define
attributes (both symbol and line style) for elements. Pens mirror the configuration
options of data elements that pertain to how symbols and lines are drawn.
Data elements use pens to determine how they are drawn. A data element
may use several pens at once. In this case, the pen used for a particular
data point is determined from each element's weight vector (see the element's
<B>-weight</B> and <B>-style</B> options). <P>
One pen, called activeLine, is automatically
created. It's used as the default active pen for elements. So you can change
the active attributes for all elements by simply reconfiguring this pen.
<BR>
<CODE>.g pen configure "activeLine" -color green<BR>
</CODE>You can create and use several pens. To create a pen, invoke the pen component
and its create operation. <BR>
<CODE>.g pen create myPen<BR>
</CODE>You map pens to a data element using either the element's <B>-pen</B> or <B>-activepen</B>
options. <BR>
<CODE>.g element create "line1" -xdata $x -ydata $tempData \<BR>
-pen myPen<BR>
</CODE>An element can use several pens at once. This is done by specifying the
name of the pen in the element's style list (see the <B>-styles</B> option). <BR>
<CODE>.g element configure "line1" -styles { myPen 2.0 3.0 }<BR>
</CODE>This says that any data point with a weight between 2.0 and 3.0 is to be
drawn using the pen myPen. All other points are drawn with the element's
default attributes. <P>
The following operations are available for pen components.
<P>
<DL>
<DT><I>pathName <B>pen <B>cget <I>penName <I>option</I></I></B></B></I> </DT>
<DD>Returns the current value of the option
given by <I>option</I> for <I>penName</I>. <I>Option</I> may be any option described below for
the pen <B>configure</B> operation. </DD>
<DT><I>pathName <B>pen <B>configure <I>penName </I></B></B></I>?<I>penName</I>... ?<I>option
value</I>?... </DT>
<DD>Queries or modifies the configuration options of <I>penName</I>. Several
pens can be modified at once. If <I>option</I> isn't specified, a list describing
the current options for <I>penName</I> is returned. If <I>option</I> is specified, but
not <I>value</I>, then a list describing <I>option</I> is returned. If one or more <I>option</I>
and <I>value</I> pairs are specified, then for each pair, the pen option <I>option</I>
is set to <I>value</I>. The following options are valid for pens. <blockquote></DD>
<DT><B>-color <I>color</I></B>
</DT>
<DD>Sets the color of the traces connecting the data points. </DD>
<DT><B>-dashes <I>dashList</I></B>
</DT>
<DD>Sets the dash style of element line. <I>DashList</I> is a list of up to 11 numbers
that alternately represent the lengths of the dashes and gaps on the element
line. Each number must be between 1 and 255. If <I>dashList</I> is "", the lines
will be solid. </DD>
<DT><B>-fill <I>color</I></B> </DT>
<DD>Sets the interior color of symbols. If <I>color</I>
is "", then the interior of the symbol is transparent. If <I>color</I> is defcolor,
then the color will be the same as the <B>-color</B> option. The default is defcolor.
</DD>
<DT><B>-linewidth <I>pixels</I></B> </DT>
<DD>Sets the width of the connecting lines between data points.
If <I>pixels</I> is 0, no connecting lines will be drawn between symbols. The
default is 0. </DD>
<DT><B>-offdash <I>color</I></B> </DT>
<DD>Sets the color of the stripes when traces
are dashed (see the <B>-dashes</B> option). If <I>color</I> is "", then the "off" pixels
will represent gaps instead of stripes. If <I>color</I> is defcolor, then the
color will be the same as the <B>-color</B> option. The default is defcolor. </DD>
<DT><B>-outline
<I>color</I></B> </DT>
<DD>Sets the color or the outline around each symbol. If <I>color</I> is "",
then no outline is drawn. If <I>color</I> is defcolor, then the color will be
the same as the <B>-color</B> option. The default is defcolor. </DD>
<DT><B>-outlinewidth <I>pixels</I></B>
</DT>
<DD>Sets the width of the outline bordering each symbol. If <I>pixels</I> is 0,
no outline will be drawn. The default is 1. </DD>
<DT><B>-pixels <I>pixels</I></B> </DT>
<DD>Sets the size
of symbols. If <I>pixels</I> is 0, no symbols will be drawn. The default is
0.125i. </DD>
<DT><B>-symbol <I>symbol</I></B> </DT>
<DD>Specifies the symbol for data points. <I>Symbol</I> can
be either square, circle, diamond, plus, cross, splus, scross,
triangle, "" (where no symbol is drawn), or a bitmap. Bitmaps are specified
as "<I>source</I> ?<I>mask</I>?", where <I>source</I> is the name of the bitmap, and <I>mask</I> is
the bitmap's optional mask. The default is circle. </DD>
<DT><B>-type <I>elemType</I></B> </DT>
<DD>Specifies
the type of element the pen is to be used with. This option should only
be employed when creating the pen. This is for those that wish to mix different
types of elements (bars and lines) on the same graph. The default type
is "line". </DD>
</DL>
<P>
Pen configuration options may be also be set by the <B>option</B> command.
The resource class is Pen. The resource names are the names of the pens.
<BR>
<CODE>option add *Graph.Pen.Color blue<BR>
option add *Graph.activeLine.color green<BR>
</blockquote>
<DL>
<DT></CODE><I>pathName <B>pen <B>create <I>penName </I></B></B></I>?<I>option value</I>?... </DT>
<DD>Creates a new pen by the name
<I>penName</I>. No pen by the same name can already exist. <I>Option</I> and <I>value</I> are
described in above in the pen <B>configure</B> operation. </DD>
<DT><I>pathName <B>pen <B>delete
</B></B></I>?<I>penName</I>?... </DT>
<DD>Deletes the named pens. A pen is not really deleted until it is
not longer in use, so it's safe to delete pens mapped to elements. </DD>
<DT><I>pathName
<B>pen names </B></I>?<I>pattern</I>?... </DT>
<DD>Returns a list of pens matching zero or more patterns.
If no <I>pattern</I> argument is give, the names of all pens are returned. </DD>
</DL>
<H3><A NAME="sect14" HREF="#toc14">PostScript
Component</A></H3>
The graph can generate encapsulated PostScript output. There are
several configuration options you can specify to control how the plot will
be generated. You can change the page dimensions and borders. The plot
itself can be scaled, centered, or rotated to landscape. The PostScript
output can be written directly to a file or returned through the interpreter.
<P>
The following postscript operations are available.
<DL>
<DT><I>pathName <B>postscript cget
<I>option</I></B></I> </DT>
<DD>Returns the current value of the postscript option given by <I>option</I>.
<I>Option</I> may be any option described below for the postscript <B>configure</B>
operation. </DD>
<DT><I>pathName <B>postscript configure </B></I>?<I>option value</I>?... </DT>
<DD>Queries or modifies
the configuration options for PostScript generation. If <I>option</I> isn't specified,
a list describing the current postscript options for <I>pathName</I> is returned.
If <I>option</I> is specified, but not <I>value</I>, then a list describing <I>option</I> is
returned. If one or more <I>option</I> and <I>value</I> pairs are specified, then for
each pair, the postscript option <I>option</I> is set to <I>value</I>. The following
postscript options are available. <blockquote></DD>
<DT><B>-center <I>boolean</I></B> </DT>
<DD>Indicates whether the plot
should be centered on the PostScript page. If <I>boolean</I> is false, the plot
will be placed in the upper left corner of the page. The default is 1.
</DD>
<DT><B>-colormap <I>varName</I></B> </DT>
<DD><I>VarName</I> must be the name of a global array variable that
specifies a color mapping from the X color name to PostScript. Each element
of <I>varName</I> must consist of PostScript code to set a particular color value
(e.g. ``1.0 1.0 0.0 setrgbcolor''). When generating color information in PostScript,
the array variable <I>varName</I> is checked if an element of the name as the
color exists. If so, it uses its value as the PostScript command to set
the color. If this option hasn't been specified, or if there isn't an entry
in <I>varName</I> for a given color, then it uses the red, green, and blue intensities
from the X color. </DD>
<DT><B>-colormode <I>mode</I></B> </DT>
<DD>Specifies how to output color information.
<I>Mode</I> must be either color (for full color output), gray (convert all
colors to their gray-scale equivalents) or mono (convert foreground colors
to black and background colors to white). The default mode is color.
</DD>
<DT><B>-fontmap <I>varName</I></B> </DT>
<DD><I>VarName</I> must be the name of a global array variable that
specifies a font mapping from the X font name to PostScript. Each element
of <I>varName</I> must consist of a Tcl list with one or two elements; the name
and point size of a PostScript font. When outputting PostScript commands
for a particular font, the array variable <I>varName</I> is checked to see if
an element by the specified font exists. If there is such an element,
then the font information contained in that element is used in the PostScript
output. (If the point size is omitted from the list, the point size of
the X font is used). Otherwise the X font is examined in an attempt to
guess what PostScript font to use. This works only for fonts whose foundry
property is <I>Adobe</I> (such as Times, Helvetica, Courier, etc.). If all of this
fails then the font defaults to Helvetica-Bold. </DD>
<DT><B>-decorations <I>boolean</I></B> </DT>
<DD>Indicates
whether PostScript commands to generate color backgrounds and 3-D borders
will be output. If <I>boolean</I> is false, the background will be white and
no 3-D borders will be generated. The default is 1. </DD>
<DT><B>-height <I>pixels</I></B> </DT>
<DD>Sets the
height of the plot. This lets you print the graph with a height different
from the one drawn on the screen. If <I>pixels</I> is 0, the height is the same
as the widget's height. The default is 0. </DD>
<DT><B>-landscape <I>boolean</I></B> </DT>
<DD>If <I>boolean</I> is
true, this specifies the printed area is to be rotated 90 degrees. In non-rotated
output the X-axis of the printed area runs along the short dimension of
the page (``portrait'' orientation); in rotated output the X-axis runs along
the long dimension of the page (``landscape'' orientation). Defaults to 0.
</DD>
<DT><B>-maxpect <I>boolean</I></B> </DT>
<DD>Indicates to scale the plot so that it fills the PostScript
page. The aspect ratio of the graph is still retained. The default is 0.
</DD>
<DT><B>-padx <I>pad</I></B> </DT>
<DD>Sets the horizontal padding for the left and right page borders.
The borders are exterior to the plot. <I>Pad</I> can be a list of one or two
screen distances. If <I>pad</I> has two elements, the left border is padded by
the first distance and the right border by the second. If <I>pad</I> has just
one distance, both the left and right borders are padded evenly. The default
is 1i. </DD>
<DT><B>-pady <I>pad</I></B> </DT>
<DD>Sets the vertical padding for the top and bottom page
borders. The borders are exterior to the plot. <I>Pad</I> can be a list of one
or two screen distances. If <I>pad</I> has two elements, the top border is padded
by the first distance and the bottom border by the second. If <I>pad</I> has just
one distance, both the top and bottom borders are padded evenly. The default
is 1i. </DD>
<DT><B>-paperheight <I>pixels</I></B> </DT>
<DD>Sets the height of the postscript page. This
can be used to select between different page sizes (letter, A4, etc). The
default height is 11.0i. </DD>
<DT><B>-paperwidth <I>pixels</I></B> </DT>
<DD>Sets the width of the postscript
page. This can be used to select between different page sizes (letter,
A4, etc). The default width is 8.5i. </DD>
<DT><B>-width <I>pixels</I></B> </DT>
<DD>Sets the width of the
plot. This lets you generate a plot of a width different from that of the
widget. If <I>pixels</I> is 0, the width is the same as the widget's width. The
default is 0. </DD>
</DL>
<P>
Postscript configuration options may be also be set by the
<B>option</B> command. The resource name and class are postscript and Postscript
respectively. <BR>
<CODE>option add *Graph.postscript.Decorations false<BR>
option add *Graph.Postscript.Landscape true<BR>
</blockquote>
<DL>
<DT></CODE><I>pathName <B>postscript output </B></I>?<I>fileName</I>? ?<I>option value</I>?... </DT>
<DD>Outputs a file of
encapsulated PostScript. If a <I>fileName</I> argument isn't present, the command
returns the PostScript. If any <I>option-value</I> pairs are present, they set configuration
options controlling how the PostScript is generated. <I>Option</I> and <I>value</I> can
be anything accepted by the postscript <B>configure</B> operation above. </DD>
</DL>
<H3><A NAME="sect15" HREF="#toc15">Marker
Components</A></H3>
Markers are simple drawing procedures used to annotate or highlight
areas of the graph. Markers have various types: text strings, bitmaps,
images, connected lines, windows, or polygons. They can be associated with
a particular element, so that when the element is hidden or un-hidden, so
is the marker. By default, markers are the last items drawn, so that data
elements will appear in behind them. You can change this by configuring
the <B>-under</B> option. <P>
Markers, in contrast to elements, don't affect the scaling
of the coordinate axes. They can also have <I>elastic</I> coordinates (specified
by -Inf and Inf respectively) that translate into the minimum or maximum
limit of the axis. For example, you can place a marker so it always remains
in the lower left corner of the plotting area, by using the coordinates
-Inf,-Inf. <P>
The following operations are available for markers.
<DL>
<DT><I>pathName
<B>marker after <I>markerId</I></B></I> ?<I>afterId</I>? </DT>
<DD>Changes the order of the markers, drawing
the first marker after the second. If no second <I>afterId</I> argument is specified,
the marker is placed at the end of the display list. This command can be
used to control how markers are displayed since markers are drawn in the
order of this display list. </DD>
<DT><I>pathName <B>marker before <I>markerId</I></B></I> ?<I>beforeId</I>? </DT>
<DD>Changes
the order of the markers, drawing the first marker before the second. If
no second <I>beforeId</I> argument is specified, the marker is placed at the beginning
of the display list. This command can be used to control how markers are
displayed since markers are drawn in the order of this display list. </DD>
<DT><I>pathName
<B>marker bind <I>tagName</I></B></I> ?<I>sequence</I>? ?<I>command</I>? </DT>
<DD>Associates <I>command</I> with <I>tagName</I>
such that whenever the event sequence given by <I>sequence</I> occurs for a marker
with this tag, <I>command</I> will be invoked. The syntax is similar to the <B>bind</B>
command except that it operates on graph markers, rather than widgets.
See the <B>bind</B> manual entry for complete details on <I>sequence</I> and the substitutions
performed on <I>command</I> before invoking it. <P>
If all arguments are specified
then a new binding is created, replacing any existing binding for the
same <I>sequence</I> and <I>tagName</I>. If the first character of <I>command</I> is + then
<I>command</I> augments an existing binding rather than replacing it. If no <I>command</I>
argument is provided then the command currently associated with <I>tagName</I>
and <I>sequence</I> (it's an error occurs if there's no such binding) is returned.
If both <I>command</I> and <I>sequence</I> are missing then a list of all the event
sequences for which bindings have been defined for <I>tagName</I>. </DD>
<DT><I>pathName <B>marker
cget <I>option</I></B></I> </DT>
<DD>Returns the current value of the marker configuration option
given by <I>option</I>. <I>Option</I> may be any option described below in the <B>configure</B>
operation. </DD>
<DT><I>pathName <B>marker configure <I>markerId</I></B></I> ?<I>option value</I>?... </DT>
<DD>Queries or
modifies the configuration options for markers. If <I>option</I> isn't specified,
a list describing the current options for <I>markerId</I> is returned. If <I>option</I>
is specified, but not <I>value</I>, then a list describing <I>option</I> is returned.
If one or more <I>option</I> and <I>value</I> pairs are specified, then for each pair,
the marker option <I>option</I> is set to <I>value</I>. <P>
The following options are valid
for all markers. Each type of marker also has its own type-specific options.
They are described in the sections below. <blockquote></DD>
<DT><B>-bindtags <I>tagList</I></B> </DT>
<DD>Specifies the
binding tags for the marker. <I>TagList</I> is a list of binding tag names. The
tags and their order will determine how events for markers are handled.
Each tag in the list matching the current event sequence will have its
Tcl command executed. Implicitly the name of the marker is always the
first tag in the list. The default value is all. </DD>
<DT><B>-coords <I>coordList</I></B> </DT>
<DD>Specifies
the coordinates of the marker. <I>CoordList</I> is a list of graph coordinates.
The number of coordinates required is dependent on the type of marker.
Text, image, and window markers need only two coordinates (an X-Y coordinate).
Bitmap markers can take either two or four coordinates (if four, they
represent the corners of the bitmap). Line markers need at least four coordinates,
polygons at least six. If <I>coordList</I> is "", the marker will not be displayed.
The default is "". </DD>
<DT><B>-element <I>elemName</I></B> </DT>
<DD>Links the marker with the element
<I>elemName</I>. The marker is drawn only if the element is also currently displayed
(see the element's <B>show</B> operation). If <I>elemName</I> is "", the marker is always
drawn. The default is "". </DD>
<DT><B>-hide <I>boolean</I></B> </DT>
<DD>Indicates whether the marker is
drawn. If <I>boolean</I> is true, the marker is not drawn. The default is no.
</DD>
<DT><B>-mapx <I>xAxis</I></B> </DT>
<DD>Specifies the X-axis to map the marker's X-coordinates onto. <I>XAxis</I>
must the name of an axis. The default is x. </DD>
<DT><B>-mapy <I>yAxis</I></B> </DT>
<DD>Specifies the Y-axis
to map the marker's Y-coordinates onto. <I>YAxis</I> must the name of an axis. The
default is y. </DD>
<DT><B>-name <I>markerId</I></B> </DT>
<DD>Changes the identifier for the marker. The
identifier <I>markerId</I> can not already be used by another marker. If this
option isn't specified, the marker's name is uniquely generated. </DD>
<DT><B>-under <I>boolean</I></B>
</DT>
<DD>Indicates whether the marker is drawn below/above data elements. If <I>boolean</I>
is true, the marker is be drawn underneath the data element symbols and
lines. Otherwise, the marker is drawn on top of the element. The default
is 0. </DD>
<DT><B>-xoffset <I>pixels</I></B> </DT>
<DD>Specifies a screen distance to offset the marker
horizontally. <I>Pixels</I> is a valid screen distance, such as 2 or 1.2i. The
default is 0. </DD>
<DT><B>-yoffset <I>pixels</I></B> </DT>
<DD>Specifies a screen distance to offset the
markers vertically. <I>Pixels</I> is a valid screen distance, such as 2 or 1.2i.
The default is 0. </DD>
</DL>
<P>
Marker configuration options may also be set by the
<B>option</B> command. The resource class is either BitmapMarker, ImageMarker,
LineMarker, PolygonMarker, TextMarker, or WindowMarker, depending
on the type of marker. The resource name is the name of the marker. <BR>
<CODE>option add *Graph.TextMarker.Foreground white<BR>
option add *Graph.BitmapMarker.Foreground white<BR>
option add *Graph.m1.Background blue<BR>
</blockquote>
<DL>
<DT></CODE><I>pathName <B>marker create <I>type</I></B></I> ?<I>option value</I>?... </DT>
<DD>Creates a marker of the selected
type. <I>Type</I> may be either text, line, bitmap, image, polygon, or
window. This command returns the marker identifier, used as the <I>markerId</I>
argument in the other marker-related commands. If the <B>-name</B> option is used,
this overrides the normal marker identifier. If the name provided is already
used for another marker, the new marker will replace the old. </DD>
<DT><I>pathName <B>marker
delete</B></I> ?<I>name</I>?... </DT>
<DD>Removes one of more markers. The graph will automatically
be redrawn without the marker.. </DD>
<DT><I>pathName <B>marker exists <I>markerId</I></B></I> </DT>
<DD>Returns
1 if the marker <I>markerId</I> exists and 0 otherwise. </DD>
<DT><I>pathName <B>marker names</B></I>
?<I>pattern</I>? </DT>
<DD>Returns the names of all the markers that currently exist.
If <I>pattern</I> is supplied, only those markers whose names match it will be
returned. </DD>
<DT><I>pathName <B>marker type <I>markerId</I></B></I> </DT>
<DD>Returns the type of the marker
given by <I>markerId</I>, such as line or text. If <I>markerId</I> is not a valid
a marker identifier, "" is returned. </DD>
</DL>
<H3><A NAME="sect16" HREF="#toc16">Bitmap Markers</A></H3>
A bitmap marker displays
a bitmap. The size of the bitmap is controlled by the number of coordinates
specified. If two coordinates, they specify the position of the top-left
corner of the bitmap. The bitmap retains its normal width and height. If
four coordinates, the first and second pairs of coordinates represent the
corners of the bitmap. The bitmap will be stretched or reduced as necessary
to fit into the bounding rectangle. <P>
Bitmap markers are created with the
marker's <B>create</B> operation in the form: <BR>
<P>
<CODE><I>pathName <B>marker create bitmap </B></I>?<I>option value</I>?...<BR>
</CODE>There may be many <I>option</I>-<I>value</I> pairs, each sets a configuration options
for the marker. These same <I>option</I>-<I>value</I> pairs may be used with the marker's
<B>configure</B> operation. <P>
The following options are specific to bitmap markers:
<DL>
<DT><B>-background <I>color</I></B> </DT>
<DD>Same as the <B>-fill</B> option. </DD>
<DT><B>-bitmap <I>bitmap</I></B> </DT>
<DD>Specifies the bitmap
to be displayed. If <I>bitmap</I> is "", the marker will not be displayed. The
default is "". </DD>
<DT><B>-fill <I>color</I></B> </DT>
<DD>Sets the background color of the bitmap. If
<I>color</I> is the empty string, no background will be transparent. The default
background color is "". </DD>
<DT><B>-foreground <I>color</I></B> </DT>
<DD>Same as the <B>-outline</B> option. </DD>
<DT><B>-mask
<I>mask</I></B> </DT>
<DD>Specifies a mask for the bitmap to be displayed. This mask is a bitmap
itself, denoting the pixels that are transparent. If <I>mask</I> is "", all
pixels of the bitmap will be drawn. The default is "". </DD>
<DT><B>-outline <I>color</I></B> </DT>
<DD>Sets
the foreground color of the bitmap. The default value is black. </DD>
<DT><B>-rotate
<I>theta</I></B> </DT>
<DD>Sets the rotation of the bitmap. <I>Theta</I> is a real number representing
the angle of rotation in degrees. The marker is first rotated and then
placed according to its anchor position. The default rotation is 0.0. </DD>
</DL>
<H3><A NAME="sect17" HREF="#toc17">Image
Markers</A></H3>
A image marker displays an image. Image markers are created with
the marker's <B>create</B> operation in the form: <BR>
<P>
<CODE><I>pathName <B>marker create image </B></I>?<I>option value</I>?...<BR>
</CODE>There may be many <I>option</I>-<I>value</I> pairs, each sets a configuration option for
the marker. These same <I>option</I>-<I>value</I> pairs may be used with the marker's <B>configure</B>
operation. <P>
The following options are specific to image markers:
<DL>
<DT><B>-anchor <I>anchor</I></B>
</DT>
<DD><I>Anchor</I> tells how to position the image relative to the positioning point
for the image. For example, if <I>anchor</I> is center then the image is centered
on the point; if <I>anchor</I> is n then the image will be drawn such that
the top center point of the rectangular region occupied by the image will
be at the positioning point. This option defaults to center. </DD>
<DT><B>-image <I>image</I></B>
</DT>
<DD>Specifies the image to be drawn. If <I>image</I> is "", the marker will not be
drawn. The default is "". </DD>
</DL>
<H3><A NAME="sect18" HREF="#toc18">Line Markers</A></H3>
A line marker displays one or more
connected line segments. Line markers are created with marker's <B>create</B> operation
in the form: <BR>
<P>
<CODE><I>pathName <B>marker create line </B></I>?<I>option value</I>?...<BR>
</CODE>There may be many <I>option</I>-<I>value</I> pairs, each sets a configuration option for
the marker. These same <I>option</I>-<I>value</I> pairs may be used with the marker's <B>configure</B>
operation. <P>
The following options are specific to line markers:
<DL>
<DT><B>-dashes <I>dashList</I></B>
</DT>
<DD>Sets the dash style of the line. <I>DashList</I> is a list of up to 11 numbers
that alternately represent the lengths of the dashes and gaps on the line.
Each number must be between 1 and 255. If <I>dashList</I> is "", the marker
line will be solid. </DD>
<DT><B>-fill <I>color</I></B> </DT>
<DD>Sets the background color of the line. This
color is used with striped lines (see the <B>-fdashes</B> option). If <I>color</I> is the
empty string, no background color is drawn (the line will be dashed, not
striped). The default background color is "". </DD>
<DT><B>-linewidth <I>pixels</I></B> </DT>
<DD>Sets the
width of the lines. The default width is 0. </DD>
<DT><B>-outline <I>color</I></B> </DT>
<DD>Sets the foreground
color of the line. The default value is black. </DD>
<DT><B>-stipple <I>bitmap</I></B> </DT>
<DD>Specifies
a stipple pattern used to draw the line, rather than a solid line. <I>Bitmap</I>
specifies a bitmap to use as the stipple pattern. If <I>bitmap</I> is "", then
the line is drawn in a solid fashion. The default is "". </DD>
</DL>
<H3><A NAME="sect19" HREF="#toc19">Polygon Markers</A></H3>
A
polygon marker displays a closed region described as two or more connected
line segments. It is assumed the first and last points are connected. Polygon
markers are created using the marker <B>create</B> operation in the form: <BR>
<P>
<CODE><I>pathName <B>marker create polygon </B></I>?<I>option value</I>?...<BR>
</CODE>There may be many <I>option</I>-<I>value</I> pairs, each sets a configuration option for
the marker. These same <I>option</I>-<I>value</I> pairs may be used with the <B>marker configure</B>
command to change the marker's configuration. The following options are supported
for polygon markers:
<DL>
<DT><B>-dashes <I>dashList</I></B> </DT>
<DD>Sets the dash style of the outline
of the polygon. <I>DashList</I> is a list of up to 11 numbers that alternately
represent the lengths of the dashes and gaps on the outline. Each number
must be between 1 and 255. If <I>dashList</I> is "", the outline will be a solid
line. </DD>
<DT><B>-fill <I>color</I></B> </DT>
<DD>Sets the fill color of the polygon. If <I>color</I> is "", then
the interior of the polygon is transparent. The default is white. </DD>
<DT><B>-linewidth
<I>pixels</I></B> </DT>
<DD>Sets the width of the outline of the polygon. If <I>pixels</I> is zero,
no outline is drawn. The default is 0. </DD>
<DT><B>-outline <I>color</I></B> </DT>
<DD>Sets the color of
the outline of the polygon. If the polygon is stippled (see the <B>-stipple</B>
option), then this represents the foreground color of the stipple. The
default is black. </DD>
<DT><B>-stipple <I>bitmap</I></B> </DT>
<DD>Specifies that the polygon should be
drawn with a stippled pattern rather than a solid color. <I>Bitmap</I> specifies
a bitmap to use as the stipple pattern. If <I>bitmap</I> is "", then the polygon
is filled with a solid color (if the <B>-fill</B> option is set). The default is
"". </DD>
</DL>
<H3><A NAME="sect20" HREF="#toc20">Text Markers</A></H3>
A text marker displays a string of characters on one or
more lines of text. Embedded newlines cause line breaks. They may be used
to annotate regions of the graph. Text markers are created with the <B>create</B>
operation in the form: <BR>
<P>
<CODE><I>pathName <B>marker create text </B></I>?<I>option value</I>?...<BR>
</CODE>There may be many <I>option</I>-<I>value</I> pairs, each sets a configuration option
for the text marker. These same <I>option</I>-<I>value</I> pairs may be used with the
marker's <B>configure</B> operation. <P>
The following options are specific to text
markers:
<DL>
<DT><B>-anchor <I>anchor</I></B> </DT>
<DD><I>Anchor</I> tells how to position the text relative to
the positioning point for the text. For example, if <I>anchor</I> is center then
the text is centered on the point; if <I>anchor</I> is n then the text will
be drawn such that the top center point of the rectangular region occupied
by the text will be at the positioning point. This default is center.
</DD>
<DT><B>-background <I>color</I></B> </DT>
<DD>Same as the <B>-fill</B> option. </DD>
<DT><B>-font <I>fontName</I></B> </DT>
<DD>Specifies the font
of the text. The default is *-Helvetica-Bold-R-Normal-*-120-*. </DD>
<DT><B>-fill <I>color</I></B> </DT>
<DD>Sets
the background color of the text. If <I>color</I> is the empty string, no background
will be transparent. The default background color is "". </DD>
<DT><B>-foreground <I>color</I></B>
</DT>
<DD>Same as the <B>-outline</B> option. </DD>
<DT><B>-justify <I>justify</I></B> </DT>
<DD>Specifies how the text should
be justified. This matters only when the marker contains more than one
line of text. <I>Justify</I> must be left, right, or center. The default
is center. </DD>
<DT><B>-outline <I>color</I></B> </DT>
<DD>Sets the color of the text. The default value
is black. </DD>
<DT><B>-padx <I>pad</I></B> </DT>
<DD>Sets the padding to the left and right exteriors of
the text. <I>Pad</I> can be a list of one or two screen distances. If <I>pad</I> has two
elements, the left side of the text is padded by the first distance and
the right side by the second. If <I>pad</I> has just one distance, both the left
and right sides are padded evenly. The default is 4. </DD>
<DT><B>-pady <I>pad</I></B> </DT>
<DD>Sets the
padding above and below the text. <I>Pad</I> can be a list of one or two screen
distances. If <I>pad</I> has two elements, the area above the text is padded by
the first distance and the area below by the second. If <I>pad</I> is just one
distance, both the top and bottom areas are padded evenly. The default
is 4. </DD>
<DT><B>-rotate <I>theta</I></B> </DT>
<DD>Specifies the number of degrees to rotate the text.
<I>Theta</I> is a real number representing the angle of rotation. The marker
is first rotated along its center and is then drawn according to its anchor
position. The default is 0.0. </DD>
<DT><B>-text <I>text</I></B> </DT>
<DD>Specifies the text of the marker.
The exact way the text is displayed may be affected by other options such
as <B>-anchor</B> or <B>-rotate</B>. </DD>
</DL>
<H3><A NAME="sect21" HREF="#toc21">Window Markers</A></H3>
A window marker displays a widget at
a given position. Window markers are created with the marker's <B>create</B> operation
in the form: <BR>
<P>
<CODE><I>pathName <B>marker create window </B></I>?<I>option value</I>?...<BR>
</CODE>There may be many <I>option</I>-<I>value</I> pairs, each sets a configuration option for
the marker. These same <I>option</I>-<I>value</I> pairs may be used with the marker's <B>configure</B>
command. <P>
The following options are specific to window markers:
<DL>
<DT><B>-anchor <I>anchor</I></B>
</DT>
<DD><I>Anchor</I> tells how to position the widget relative to the positioning point
for the widget. For example, if <I>anchor</I> is center then the widget is centered
on the point; if <I>anchor</I> is n then the widget will be displayed such that
the top center point of the rectangular region occupied by the widget will
be at the positioning point. This option defaults to center. </DD>
<DT><B>-height <I>pixels</I></B>
</DT>
<DD>Specifies the height to assign to the marker's window. If this option isn't
specified, or if it is specified as "", then the window is given whatever
height the widget requests internally. </DD>
<DT><B>-width <I>pixels</I></B> </DT>
<DD>Specifies the width
to assign to the marker's window. If this option isn't specified, or if it
is specified as "", then the window is given whatever width the widget
requests internally. </DD>
<DT><B>-window <I>pathName</I></B> </DT>
<DD>Specifies the widget to be managed
by the graph. <I>PathName</I> must be a child of the <B>graph</B> widget. </DD>
</DL>
<H2><A NAME="sect22" HREF="#toc22">Graph Component
Bindings</A></H2>
Specific graph components, such as elements, markers and legend
entries, can have a command trigger when event occurs in them, much like
canvas items in Tk's canvas widget. Not all event sequences are valid. The
only binding events that may be specified are those related to the mouse
and keyboard (such as <B>Enter</B>, <B>Leave</B>, <B>ButtonPress</B>, <B>Motion</B>, and <B>KeyPress</B>).
<P>
Only one element or marker can be picked during an event. This means, that
if the mouse is directly over both an element and a marker, only the uppermost
component is selected. This isn't true for legend entries. Both a legend
entry and an element (or marker) binding commands will be invoked if both
items are picked. <P>
It is possible for multiple bindings to match a particular
event. This could occur, for example, if one binding is associated with
the element name and another is associated with one of the element's tags
(see the <B>-bindtags</B> option). When this occurs, all of the matching bindings
are invoked. A binding associated with the element name is invoked first,
followed by one binding for each of the element's bindtags. If there are
multiple matching bindings for a single tag, then only the most specific
binding is invoked. A continue command in a binding script terminates
that script, and a break command terminates that script and skips any
remaining scripts for the event, just as for the bind command. <P>
The <B>-bindtags</B>
option for these components controls addition tag names which can be matched.
Implicitly elements and markers always have tags matching their names.
Setting the value of the <B>-bindtags</B> option doesn't change this.
<H2><A NAME="sect23" HREF="#toc23">C Language
API</A></H2>
You can manipulate data elements from the C language. There may be situations
where it is too expensive to translate the data values from ASCII strings.
Or you might want to read data in a special file format. <P>
Data can manipulated
from the C language using BLT vectors. You specify the X-Y data coordinates
of an element as vectors and manipulate the vector from C. The graph will
be redrawn automatically after the vectors are updated. <P>
From Tcl, create
the vectors and configure the element to use them. <BR>
<CODE>vector X Y<BR>
.g element configure line1 -xdata X -ydata Y<BR>
</CODE>To set data points from C, you pass the values as arrays of doubles using
the <B>Blt_ResetVector</B> call. The vector is reset with the new data and at
the next idle point (when Tk re-enters its event loop), the graph will be
redrawn automatically. <BR>
<CODE>#include <tcl.h><BR>
#include <blt.h><BR>
<P>
register int i;<BR>
Blt_Vector *xVec, *yVec;<BR>
double x[50], y[50];<BR>
<P>
/* Get the BLT vectors "X" and "Y" (created above from Tcl) */<BR>
if ((Blt_GetVector(interp, "X", &xVec) != TCL_OK) ||<BR>
(Blt_GetVector(interp, "Y", &yVec) != TCL_OK)) {<BR>
return TCL_ERROR;<BR>
}<BR>
<P>
for (i = 0; i < 50; i++) {<BR>
x[i] = i * 0.02;<BR>
y[i] = sin(x[i]);<BR>
}<tt> </tt> <tt> </tt> <BR>
<P>
/* Put the data into BLT vectors */<BR>
if ((Blt_ResetVector(xVec, x, 50, 50, TCL_VOLATILE) != TCL_OK) ||<BR>
(Blt_ResetVector(yVec, y, 50, 50, TCL_VOLATILE) != TCL_OK)) {<BR>
return TCL_ERROR;<BR>
}<BR>
</CODE>See the <B>vector</B> manual page for more details.
<H2><A NAME="sect24" HREF="#toc24">Speed Tips</A></H2>
There may be cases
where the graph needs to be drawn and updated as quickly as possible. If
drawing speed becomes a big problem, here are a few tips to speed up displays.
<UL>
<LI>Try to minimize the number of data points. The more data points the looked
at, the more work the graph must do. </LI><LI>If your data is generated as floating
point values, the time required to convert the data values to and from
ASCII strings can be significant, especially when there any many data points.
You can avoid the redundant string-to-decimal conversions using the C API
to BLT vectors. </LI><LI>Data elements without symbols are drawn faster than with
symbols. Set the data element's <B>-symbol</B> option to none. If you need to draw
symbols, try using the simple symbols such as splus and scross. </LI><LI>Don't
stipple or dash the element. Solid lines are much faster. </LI><LI>If you update
data elements frequently, try turning off the widget's <B>-bufferelements</B> option.
When the graph is first displayed, it draws data elements into an internal
pixmap. The pixmap acts as a cache, so that when the graph needs to be
redrawn again, and the data elements or coordinate axes haven't changed,
the pixmap is simply copied to the screen. This is especially useful when
you are using markers to highlight points and regions on the graph. But
if the graph is updated frequently, changing either the element data or
coordinate axes, the buffering becomes redundant. </LI>
</UL>
<H2><A NAME="sect25" HREF="#toc25">Limitations</A></H2>
Auto-scale routines
do not use requested min/max limits as boundaries when the axis is logarithmically
scaled. <P>
The PostScript output generated for polygons with more than 1500
points may exceed the limits of some printers (See PostScript Language
Reference Manual, page 568). The work-around is to break the polygon into
separate pieces.
<H2><A NAME="sect26" HREF="#toc26">Keywords</A></H2>
graph, widget <P>
<HR><P>
<A NAME="toc"><B>Table of Contents</B></A><P>
<UL>
<LI><A NAME="toc0" HREF="#sect0">Name</A></LI>
<LI><A NAME="toc1" HREF="#sect1">Synopsis</A></LI>
<LI><A NAME="toc2" HREF="#sect2">Description</A></LI>
<LI><A NAME="toc3" HREF="#sect3">Introduction</A></LI>
<LI><A NAME="toc4" HREF="#sect4">Syntax</A></LI>
<LI><A NAME="toc5" HREF="#sect5">Example</A></LI>
<LI><A NAME="toc6" HREF="#sect6">Graph Operations</A></LI>
<LI><A NAME="toc7" HREF="#sect7">Graph Components</A></LI>
<UL>
<LI><A NAME="toc8" HREF="#sect8">Axis Components</A></LI>
<LI><A NAME="toc9" HREF="#sect9">Crosshairs Component</A></LI>
<LI><A NAME="toc10" HREF="#sect10">Element Components</A></LI>
<LI><A NAME="toc11" HREF="#sect11">Grid Component</A></LI>
<LI><A NAME="toc12" HREF="#sect12">Legend Component</A></LI>
<LI><A NAME="toc13" HREF="#sect13">Pen Components</A></LI>
<LI><A NAME="toc14" HREF="#sect14">PostScript Component</A></LI>
<LI><A NAME="toc15" HREF="#sect15">Marker Components</A></LI>
<LI><A NAME="toc16" HREF="#sect16">Bitmap Markers</A></LI>
<LI><A NAME="toc17" HREF="#sect17">Image Markers</A></LI>
<LI><A NAME="toc18" HREF="#sect18">Line Markers</A></LI>
<LI><A NAME="toc19" HREF="#sect19">Polygon Markers</A></LI>
<LI><A NAME="toc20" HREF="#sect20">Text Markers</A></LI>
<LI><A NAME="toc21" HREF="#sect21">Window Markers</A></LI>
</UL>
<LI><A NAME="toc22" HREF="#sect22">Graph Component Bindings</A></LI>
<LI><A NAME="toc23" HREF="#sect23">C Language API</A></LI>
<LI><A NAME="toc24" HREF="#sect24">Speed Tips</A></LI>
<LI><A NAME="toc25" HREF="#sect25">Limitations</A></LI>
<LI><A NAME="toc26" HREF="#sect26">Keywords</A></LI>
</UL>
</BODY></HTML>
|