This file is indexed.

/usr/share/octave/packages/interval-1.4.1/@infsup/setxor.m is in octave-interval 1.4.1-1.

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
## Copyright 2015-2016 Oliver Heimlich
##
## This program is free software; you can redistribute it and/or modify
## it under the terms of the GNU General Public License as published by
## the Free Software Foundation; either version 3 of the License, or
## (at your option) any later version.
##
## This program is distributed in the hope that it will be useful,
## but WITHOUT ANY WARRANTY; without even the implied warranty of
## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
## GNU General Public License for more details.
##
## You should have received a copy of the GNU General Public License
## along with this program; if not, see <http://www.gnu.org/licenses/>.

## -*- texinfo -*-
## @documentencoding UTF-8
## @deftypemethod {@@infsup} {} setxor (@var{A}, @var{B})
## @deftypemethodx {@@infsup} {[@var{C}, @var{C1}, @var{C2}] =} setxor (@var{A}, @var{B})
## 
## Build the symmetric difference of intervals @var{A} and @var{B}.
##
## With three output arguments, return intervals @var{C1} and @var{C2} such
## that @var{C1} and @var{C2} are enclosures of disjoint sets whose union is
## enclosed by interval @var{C}.
##
## Accuracy: The result is a tight enclosure.
##
## @example
## @group
## x = infsup (1, 3);
## y = infsup (2, 4);
## [z, z1, z2] = setxor (x, y)
##   @result{}
##     z = [1, 4]
##     z1 = [1, 2]
##     z2 = [3, 4]
## @end group
## @end example
## @seealso{@@infsup/intersect, @@infsup/union, @@infsup/setdiff}
## @end deftypemethod

## Author: Oliver Heimlich
## Keywords: interval
## Created: 2015-04-03

function [c, c1, c2] = setxor (a, b)

if (nargin ~= 2)
    print_usage ();
    return
endif
if (not (isa (a, "infsup")))
    a = infsup (a);
endif
if (not (isa (b, "infsup")))
    b = infsup (b);
endif

## Resize, if scalar × matrix
if (isscalar (a.inf) ~= isscalar (b.inf))
    a.inf = ones (size (b.inf)) .* a.inf;
    a.sup = ones (size (b.inf)) .* a.sup;
    b.inf = ones (size (a.inf)) .* b.inf;
    b.sup = ones (size (a.inf)) .* b.sup;
endif

## Sort the four boundaries in ascending order b1 <= b2 <= b3 <= b4,
## if only one empty interval is present, then [b2, b3] = [Empty],
## with two empty intervals we also have [b1, b4] = [Empty].
b1 = min (a.inf, b.inf);
b2 = max (a.inf, b.inf);
b3 = min (a.sup, b.sup);
b4 = max (a.sup, b.sup);
[b2, b3] = deal (min (b2, b3), max (b2, b3));

l = b1;
u = b4;

select = a.inf == b.inf;
l (select) = b3 (select);

select = a.sup == b.sup;
u (select) = b2 (select);

select = a.inf == b.inf & a.sup == b.sup;
l (select) = inf;
u (select) = -inf;

c = infsup (l, u);

if (nargout > 1)
    select = isempty (a) | isempty (b);
    b1 (select) = a.inf (select);
    b2 (select) = a.sup (select);
    b3 (select) = b.inf (select);
    b4 (select) = b.sup (select);

    l1 = b1;
    u1 = b2;
    select = a.inf == b.inf;
    l1 (select) = inf;
    u1 (select) = -inf;
    c1 = infsup (l1, u1);
    
    l2 = b3;
    u2 = b4;
    select = a.sup == b.sup;
    l2 (select) = inf;
    u2 (select) = -inf;
    c2 = infsup (l2, u2);
endif

endfunction

%!test
%! [z, z1, z2] = setxor (infsup (), infsup ());
%! assert (isempty (z));
%! assert (isempty (z1));
%! assert (isempty (z2));
%!test
%! [z, z1, z2] = setxor (infsup (-inf, inf), infsup ());
%! assert (isentire (z));
%! assert (isentire (z1));
%! assert (isempty (z2));
%!test
%! [z, z1, z2] = setxor (infsup (-inf, inf), infsup (2));
%! assert (isentire (z));
%! assert (z1 == infsup (-inf, 2));
%! assert (z2 == infsup (2, inf));
%!test
%! [z, z1, z2] = setxor (infsup (2, 3), infsup (2));
%! assert (z == infsup (2, 3));
%! assert (z1 == infsup ());
%! assert (z2 == infsup (2, 3));
%!test
%! [z, z1, z2] = setxor (infsup (2, 3), infsup (2, 2.5));
%! assert (z == infsup (2.5, 3));
%! assert (z1 == infsup ());
%! assert (z2 == infsup (2.5, 3));
%!test "from the documentation string";
%! [z, z1, z2] = setxor (infsup (1, 3), infsup (2, 4));
%! assert (z == infsup (1, 4));
%! assert (z1 == infsup (1, 2));
%! assert (z2 == infsup (3, 4));