This file is indexed.

/usr/include/deal.II/hp/dof_handler.h is in libdeal.ii-dev 8.1.0-6ubuntu1.

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
// ---------------------------------------------------------------------
// $Id: dof_handler.h 31932 2013-12-08 02:15:54Z heister $
//
// Copyright (C) 2005 - 2013 by the deal.II authors
//
// This file is part of the deal.II library.
//
// The deal.II library is free software; you can use it, redistribute
// it, and/or modify it under the terms of the GNU Lesser General
// Public License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
// The full text of the license can be found in the file LICENSE at
// the top level of the deal.II distribution.
//
// ---------------------------------------------------------------------

#ifndef __deal2__hp_dof_handler_h
#define __deal2__hp_dof_handler_h



#include <deal.II/base/config.h>
#include <deal.II/base/exceptions.h>
#include <deal.II/base/template_constraints.h>
#include <deal.II/base/smartpointer.h>
#include <deal.II/dofs/function_map.h>
#include <deal.II/dofs/dof_iterator_selector.h>
#include <deal.II/dofs/number_cache.h>
#include <deal.II/hp/fe_collection.h>

#include <vector>
#include <map>
#include <set>

DEAL_II_NAMESPACE_OPEN

namespace internal
{
  namespace hp
  {
    class DoFLevel;
    template <int> class DoFIndicesOnFaces;
    template <int> class DoFIndicesOnFacesOrEdges;

    namespace DoFHandler
    {
      struct Implementation;
    }
  }
}

namespace internal
{
  namespace DoFAccessor
  {
    struct Implementation;
  }

  namespace DoFCellAccessor
  {
    struct Implementation;
  }
}



namespace hp
{

  /**
   * Manage the distribution and numbering of the degrees of freedom for
   * hp-FEM algorithms.
   *
   * This class has not yet been implemented for the use in the codimension
   * one case (<tt>spacedim != dim </tt>).
   *
   * @ingroup dofs
   * @ingroup hp
   */
  template <int dim, int spacedim=dim>
  class DoFHandler : public Subscriptor
  {
    typedef dealii::internal::DoFHandler::Iterators<DoFHandler<dim,spacedim>, false> ActiveSelector;
    typedef dealii::internal::DoFHandler::Iterators<DoFHandler<dim,spacedim>, true> LevelSelector;
  public:
    typedef typename ActiveSelector::CellAccessor         cell_accessor;
    typedef typename ActiveSelector::FaceAccessor         face_accessor;

    typedef typename ActiveSelector::line_iterator        line_iterator;
    typedef typename ActiveSelector::active_line_iterator active_line_iterator;

    typedef typename ActiveSelector::quad_iterator        quad_iterator;
    typedef typename ActiveSelector::active_quad_iterator active_quad_iterator;

    typedef typename ActiveSelector::hex_iterator         hex_iterator;
    typedef typename ActiveSelector::active_hex_iterator  active_hex_iterator;

    typedef typename ActiveSelector::active_cell_iterator active_cell_iterator;

    typedef typename ActiveSelector::face_iterator        face_iterator;
    typedef typename ActiveSelector::active_face_iterator active_face_iterator;

    typedef typename LevelSelector::CellAccessor          level_cell_accessor;
    typedef typename LevelSelector::FaceAccessor          level_face_accessor;

    typedef typename LevelSelector::cell_iterator         level_cell_iterator;
    typedef typename LevelSelector::face_iterator         level_face_iterator;

    typedef level_cell_iterator                           cell_iterator;

    /**
     * Alias the @p FunctionMap type
     * declared elsewhere.
     */
    typedef typename FunctionMap<spacedim>::type FunctionMap;

    /**
     * Make the dimension available
     * in function templates.
     */
    static const unsigned int dimension = dim;

    /**
     * Make the space dimension available
     * in function templates.
     */
    static const unsigned int space_dimension = spacedim;

    /**
     * When the arrays holding the
     * DoF indices are set up, but
     * before they are filled with
     * actual values, they are set to
     * an invalid value, in order to
     * monitor possible
     * problems. This invalid value
     * is the constant defined here.
     *
     * Please note that you should
     * not rely on it having a
     * certain value, but rather take
     * its symbolic name.
     */
    static const types::global_dof_index invalid_dof_index = numbers::invalid_dof_index;

    /**
     * The default index of the
     * finite element to be used on
     * a given cell. For the usual,
     * non-hp dealii::DoFHandler class
     * that only supports the same
     * finite element to be used on
     * all cells, the index of the
     * finite element needs to be
     * the same on all cells
     * anyway, and by convention we
     * pick zero for this
     * value. The situation here is
     * different, since the hp
     * classes support the case
     * where different finite
     * element indices may be used
     * on different cells. The
     * default index consequently
     * corresponds to an invalid
     * value.
     */
    static const unsigned int default_fe_index = numbers::invalid_unsigned_int;


    /**
     * Constructor. Take @p tria as the
     * triangulation to work on.
     */
    DoFHandler (const Triangulation<dim,spacedim> &tria);

    /**
     * Destructor.
     */
    virtual ~DoFHandler ();

    /**
     * Go through the triangulation and "distribute" the degrees of
     * freedoms needed for the given finite element. "Distributing"
     * degrees of freedom involved allocating memory to store the
     * information that describes it (e.g., whether it is located on a
     * vertex, edge, face, etc) and to sequentially enumerate all
     * degrees of freedom. In other words, while the mesh and the finite
     * element object by themselves simply define a finite element space
     * $V_h$, the process of distributing degrees of freedom makes sure
     * that there is a basis for this space and that the shape functions
     * of this basis are enumerated in an indexable, predictable way.
     *
     * The purpose of this function
     * is first discussed in the introduction
     * to the step-2 tutorial program.
     *
     * @note A pointer of the finite element given as argument is
     * stored. Therefore, the lifetime of the finite element object
     * shall be longer than that of this object. If you don't want this
     * behavior, you may want to call the @p clear member function which
     * also releases the lock of this object to the finite element.
     */
    virtual void distribute_dofs (const hp::FECollection<dim,spacedim> &fe);

    /**
     * Go through the triangulation and set
     * the active FE indices of all active
     * cells to the values given in @p
     * active_fe_indices.
     */
    void set_active_fe_indices (const std::vector<unsigned int> &active_fe_indices);

    /**
     * Go through the triangulation and
     * store the active FE indices of all
     * active cells to the vector @p
     * active_fe_indices. This vector is
     * resized, if necessary.
     */
    void get_active_fe_indices (std::vector<unsigned int> &active_fe_indices) const;

    /**
     * Clear all data of this object and
     * especially delete the lock this object
     * has to the finite element used the last
     * time when @p distribute_dofs was called.
     */
    virtual void clear ();

    /**
     * Renumber degrees of freedom based on
     * a list of new dof numbers for all the
     * dofs.
     *
     * @p new_numbers is an array of integers
     * with size equal to the number of dofs
     * on the present grid. It stores the new
     * indices after renumbering in the
     * order of the old indices.
     *
     * This function is called by
     * the functions in
     * DoFRenumbering function
     * after computing the ordering
     * of the degrees of freedom.
     * However, you can call this
     * function yourself, which is
     * necessary if a user wants to
     * implement an ordering scheme
     * herself, for example
     * downwind numbering.
     *
     * The @p new_number array must
     * have a size equal to the
     * number of degrees of
     * freedom. Each entry must
     * state the new global DoF
     * number of the degree of
     * freedom referenced.
     */
    void renumber_dofs (const std::vector<types::global_dof_index> &new_numbers);

    /**
     * Return the maximum number of
     * degrees of freedom a degree of freedom
     * in the given triangulation with the
     * given finite element may couple with.
     * This is the maximum number of entries
     * per line in the system matrix; this
     * information can therefore be used upon
     * construction of the SparsityPattern
     * object.
     *
     * The returned number is not really the
     * maximum number but an estimate based
     * on the finite element and the maximum
     * number of cells meeting at a vertex.
     * The number holds for the constrained
     * matrix also.
     *
     * As for
     * ::DoFHandler::max_couplings_between_dofs(),
     * the result of this function is often
     * not very accurate for 3d and/or high
     * polynomial degrees. The consequences
     * are discussed in the documentation
     * of the module on @ref Sparsity.
     */
    unsigned int max_couplings_between_dofs () const;

    /**
     * Return the number of degrees of freedom
     * located on the boundary another dof on
     * the boundary can couple with.
     *
     * The number is the same as for
     * @p max_coupling_between_dofs in one
     * dimension less.
     *
     * @note The same applies to this function as to max_couplings_per_dofs()
     * as regards the performance of this function. Think about one of the
     * dynamic sparsity pattern classes instead (see @ref Sparsity).
     */
    unsigned int max_couplings_between_boundary_dofs () const;

    /**
    *  @name Cell iterator functions
    */
    /*@{*/
    /**
    * Iterator to the first used
    * cell on level @p level.
    */
    cell_iterator        begin       (const unsigned int level = 0) const;

    /**
     *  Iterator to the first active cell on level @p level. If the
     *  given level does not contain any active cells (i.e., all cells
     *  on this level are further refined, then this function returns
     *  <code>end_active(level)</code> so that loops of the kind
     *  @code
     *    for (cell=dof_handler.begin_active(level); cell!=dof_handler.end_active(level); ++cell)
     *      ...
     *  @endcode
     *  have zero iterations, as may be expected if there are no active
     *  cells on this level.
     */
    active_cell_iterator begin_active(const unsigned int level = 0) const;

    /**
    * Iterator past the end; this
    * iterator serves for
    * comparisons of iterators with
    * past-the-end or
    * before-the-beginning states.
    */
    cell_iterator        end () const;

    /**
    * Return an iterator which is
    * the first iterator not on
    * level. If @p level is the
    * last level, then this returns
    * <tt>end()</tt>.
    */
    cell_iterator        end (const unsigned int level) const;

    /**
     * Return an active iterator which is the first active iterator not
     * on the given level. If @p level is the last level, then this
     * returns <tt>end()</tt>.
     */
    active_cell_iterator end_active (const unsigned int level) const;

    /*@}*/

    /*---------------------------------------*/


    /**
     * Return the global number of
     * degrees of freedom. If the
     * current object handles all
     * degrees of freedom itself
     * (even if you may intend to
     * solve your linear system in
     * parallel, such as in step-17
     * or step-18), then this number
     * equals the number of locally
     * owned degrees of freedom since
     * this object doesn't know
     * anything about what you want
     * to do with it and believes
     * that it owns every degree of
     * freedom it knows about.
     *
     * On the other hand, if this
     * object operates on a
     * parallel::distributed::Triangulation
     * object, then this function
     * returns the global number of
     * degrees of freedom,
     * accumulated over all
     * processors.
     *
     * In either case, included in
     * the returned number are those
     * DoFs which are constrained by
     * hanging nodes, see @ref constraints.
     */
    types::global_dof_index n_dofs () const;

    /**
    * The number of multilevel
    * dofs on given level. Since
    * hp::DoFHandler does not
    * support multilevel methods
    * yet, this function returns
    * numbers::invalid_unsigned
    * int independent of its argument.
    */
    types::global_dof_index n_dofs(const unsigned int level) const;

    /**
     * Return the number of degrees of freedom
     * located on the boundary.
     */
    types::global_dof_index n_boundary_dofs () const;

    /**
     * Return the number of degrees
     * of freedom located on those
     * parts of the boundary which
     * have a boundary indicator
     * listed in the given set. The
     * reason that a @p map rather
     * than a @p set is used is the
     * same as described in the
     * section on the
     * @p make_boundary_sparsity_pattern
     * function.
     */
    types::global_dof_index
    n_boundary_dofs (const FunctionMap &boundary_indicators) const;

    /**
     * Same function, but with
     * different data type of the
     * argument, which is here simply
     * a list of the boundary
     * indicators under
     * consideration.
     */
    types::global_dof_index
    n_boundary_dofs (const std::set<types::boundary_id> &boundary_indicators) const;

    /**
     * Return the number of
     * degrees of freedom that
     * belong to this
     * process.
     *
     * If this is a sequential job,
     * then the result equals that
     * produced by n_dofs(). On the
     * other hand, if we are
     * operating on a
     * parallel::distributed::Triangulation,
     * then it includes only the
     * degrees of freedom that the
     * current processor owns. Note
     * that in this case this does
     * not include all degrees of
     * freedom that have been
     * distributed on the current
     * processor's image of the mesh:
     * in particular, some of the
     * degrees of freedom on the
     * interface between the cells
     * owned by this processor and
     * cells owned by other
     * processors may be theirs, and
     * degrees of freedom on ghost
     * cells are also not necessarily
     * included.
     */
    types::global_dof_index n_locally_owned_dofs() const;

    /**
     * Return an IndexSet describing
     * the set of locally owned DoFs
     * as a subset of
     * 0..n_dofs(). The number of
     * elements of this set equals
     * n_locally_owned_dofs().
     */
    const IndexSet &locally_owned_dofs() const;


    /**
     * Returns a vector that
     * stores the locally owned
     * DoFs of each processor. If
     * you are only interested in
     * the number of elements
     * each processor owns then
     * n_dofs_per_processor() is
     * a better choice.
     *
     * If this is a sequential job,
     * then the vector has a single
     * element that equals the
     * IndexSet representing the
     * entire range [0,n_dofs()].
     */
    const std::vector<IndexSet> &
    locally_owned_dofs_per_processor () const;

    /**
     * Return a vector that
     * stores the number of
     * degrees of freedom each
     * processor that
     * participates in this
     * triangulation owns
     * locally. The sum of all
     * these numbers equals the
     * number of degrees of
     * freedom that exist
     * globally, i.e. what
     * n_dofs() returns.
     *
     * Each element of the vector
     * returned by this function
     * equals the number of
     * elements of the
     * corresponding sets
     * returned by
     * global_dof_indices().
     *
     * If this is a sequential job,
     * then the vector has a single
     * element equal to n_dofs().
     */
    const std::vector<types::global_dof_index> &
    n_locally_owned_dofs_per_processor () const;

    /**
     * Return a constant reference to
     * the set of finite element
     * objects that are used by this
     * @p DoFHandler.
     */
    const hp::FECollection<dim,spacedim> &get_fe () const;

    /**
     * Return a constant reference to the
     * triangulation underlying this object.
     */
    const Triangulation<dim,spacedim> &get_tria () const;

    /**
     * Determine an estimate for the
     * memory consumption (in bytes)
     * of this object.
     *
     * This function is made virtual,
     * since a dof handler object
     * might be accessed through a
     * pointers to thisr base class,
     * although the actual object
     * might be a derived class.
     */
    virtual std::size_t memory_consumption () const;

    /**
     * Exception
     */
    DeclException0 (ExcInvalidTriangulation);
    /**
     * Exception
     */
    DeclException0 (ExcNoFESelected);
    /**
     * Exception
     */
    DeclException0 (ExcRenumberingIncomplete);
    /**
     * Exception
     */
    DeclException0 (ExcGridsDoNotMatch);
    /**
     * Exception
     */
    DeclException0 (ExcInvalidBoundaryIndicator);
    /**
     * Exception
     */
    DeclException1 (ExcMatrixHasWrongSize,
                    int,
                    << "The matrix has the wrong dimension " << arg1);
    /**
     *  Exception
     */
    DeclException0 (ExcFunctionNotUseful);
    /**
     * Exception
     */
    DeclException1 (ExcNewNumbersNotConsecutive,
                    types::global_dof_index,
                    << "The given list of new dof indices is not consecutive: "
                    << "the index " << arg1 << " does not exist.");
    /**
     * Exception
     */
    DeclException2 (ExcInvalidFEIndex,
                    int, int,
                    << "The mesh contains a cell with an active_fe_index of "
                    << arg1 << ", but the finite element collection only has "
                    << arg2 << " elements");
    /**
     *  Exception
     */
    DeclException1 (ExcInvalidLevel,
                    int,
                    << "The given level " << arg1
                    << " is not in the valid range!");
    /**
     * Exception
     */
    DeclException0 (ExcFacesHaveNoLevel);
    /**
     * The triangulation level you
     * accessed is empty.
     */
    DeclException1 (ExcEmptyLevel,
                    int,
                    << "You tried to do something on level " << arg1
                    << ", but this level is empty.");

  protected:

    /**
     * Address of the triangulation to
     * work on.
     */
    SmartPointer<const Triangulation<dim,spacedim>,DoFHandler<dim,spacedim> > tria;

    /**
     * Store a pointer to the finite
     * element set given latest for
     * the distribution of dofs. In
     * order to avoid destruction of
     * the object before the lifetime
     * of the DoF handler, we
     * subscribe to the finite
     * element object. To unlock the
     * FE before the end of the
     * lifetime of this DoF handler,
     * use the <tt>clear()</tt> function
     * (this clears all data of this
     * object as well, though).
     */
    SmartPointer<const hp::FECollection<dim,spacedim>,hp::DoFHandler<dim,spacedim> > finite_elements;

  private:

    /**
     * Copy constructor. I can see no reason
     * why someone might want to use it, so
     * I don't provide it. Since this class
     * has pointer members, making it private
     * prevents the compiler to provide it's
     * own, incorrect one if anyone chose to
     * copy such an object.
     */
    DoFHandler (const DoFHandler &);

    /**
     * Copy operator. I can see no reason
     * why someone might want to use it, so
     * I don't provide it. Since this class
     * has pointer members, making it private
     * prevents the compiler to provide it's
     * own, incorrect one if anyone chose to
     * copy such an object.
     */
    DoFHandler &operator = (const DoFHandler &);

    class MGVertexDoFs
    {
    public:
      MGVertexDoFs ();
      ~MGVertexDoFs ();
      types::global_dof_index get_index (const unsigned int level, const unsigned int dof_number) const;
      void set_index (const unsigned int level, const unsigned int dof_number, const types::global_dof_index index);
    };

    /**
     * Free all used memory.
     */
    void clear_space ();

    template<int structdim>
    types::global_dof_index get_dof_index (const unsigned int obj_level, const unsigned int obj_index, const unsigned int fe_index, const unsigned int local_index) const;

    template<int structdim>
    void set_dof_index (const unsigned int obj_level, const unsigned int obj_index, const unsigned int fe_index, const unsigned int local_index, const types::global_dof_index global_index) const;

    /**
     *  Create default tables for
     *  the active_fe_indices in
     *  the
     *  dealii::internal::hp::DoFLevel. They
     *  are initialized with a
     *  zero indicator, meaning
     *  that fe[0] is going to be
     *  used by default.  This
     *  method is called before
     *  refinement and before
     *  distribute_dofs is
     *  called. It ensures each
     *  cell has a valid
     *  active_fe_index.
     */
    void create_active_fe_table ();

    /**
     *  Functions that will be triggered
     *  through signals whenever the
     *  triangulation is modified.
     *
     *  Here they are used to
     *  administrate the the
     *  active_fe_fields during the
     *  spatial refinement.
     */
    void pre_refinement_action ();
    void post_refinement_action ();

    /**
     * Compute identities between
     * DoFs located on
     * vertices. Called from
     * distribute_dofs().
     */
    void
    compute_vertex_dof_identities (std::vector<types::global_dof_index> &new_dof_indices) const;

    /**
     * Compute identities between
     * DoFs located on
     * lines. Called from
     * distribute_dofs().
     */
    void
    compute_line_dof_identities (std::vector<types::global_dof_index> &new_dof_indices) const;

    /**
     * Compute identities between
     * DoFs located on
     * quads. Called from
     * distribute_dofs().
     */
    void
    compute_quad_dof_identities (std::vector<types::global_dof_index> &new_dof_indices) const;

    /**
     * Renumber the objects with
     * the given and all lower
     * structural dimensions,
     * i.e. renumber vertices by
     * giving a template argument
     * of zero to the int2type
     * argument, lines and vertices
     * with one, etc.
     *
     * Note that in contrast to the
     * public renumber_dofs()
     * function, these internal
     * functions do not ensure that
     * the new DoFs are
     * contiguously numbered. The
     * function may therefore also
     * be used to assign different
     * DoFs the same number, for
     * example to unify hp DoFs
     * corresponding to different
     * finite elements but
     * co-located on the same
     * entity.
     */
    void renumber_dofs_internal (const std::vector<types::global_dof_index> &new_numbers,
                                 dealii::internal::int2type<0>);

    void renumber_dofs_internal (const std::vector<types::global_dof_index> &new_numbers,
                                 dealii::internal::int2type<1>);

    void renumber_dofs_internal (const std::vector<types::global_dof_index> &new_numbers,
                                 dealii::internal::int2type<2>);

    void renumber_dofs_internal (const std::vector<types::global_dof_index> &new_numbers,
                                 dealii::internal::int2type<3>);

    /**
     * Space to store the DoF
     * numbers for the different
     * levels. Analogous to the
     * <tt>levels[]</tt> tree of
     * the Triangulation objects.
     */
    std::vector<dealii::internal::hp::DoFLevel *> levels;

    /**
     * Space to store the DoF
     * numbers for the faces.
     * Analogous to the
     * <tt>faces</tt> pointer of
     * the Triangulation objects.
     */
    dealii::internal::hp::DoFIndicesOnFaces<dim> *faces;

    /**
     * A structure that contains all
     * sorts of numbers that
     * characterize the degrees of
     * freedom this object works on.
     *
     * For most members of this
     * structure, there is an
     * accessor function in this
     * class that returns its value.
     */
    dealii::internal::DoFHandler::NumberCache number_cache;

    /**
     * Array to store the indices
     * for degrees of freedom
     * located at vertices.
     *
     * The format used here, in the
     * form of a linked list, is
     * the same as used for the
     * arrays used in the
     * internal::hp::DoFLevel
     * hierarchy. Starting indices
     * into this array are provided
     * by the vertex_dofs_offsets
     * field.
     *
     * Access to this field is
     * generally through the
     * DoFAccessor::get_vertex_dof_index() and
     * DoFAccessor::set_vertex_dof_index()
     * functions, encapsulating the
     * actual data format used to
     * the present class.
     */
    std::vector<types::global_dof_index> vertex_dofs;

    /**
     * For each vertex in the
     * triangulation, store the
     * offset within the
     * vertex_dofs array where the
     * dofs for this vertex start.
     *
     * As for that array, the
     * format is the same as
     * described in the
     * documentation of
     * hp::DoFLevel.
     *
     * Access to this field is
     * generally through the
     * Accessor::get_vertex_dof_index() and
     * Accessor::set_vertex_dof_index()
     * functions, encapsulating the
     * actual data format used to
     * the present class.
     */
    std::vector<types::global_dof_index>      vertex_dofs_offsets;

    std::vector<MGVertexDoFs> mg_vertex_dofs;

    /**
     * Array to store the
     * information if a cell on
     * some level has children or
     * not. It is used by the
     * signal slots as a
     * persistent buffer during the
     * refinement, i.e. from between
     * when pre_refinement_action is
     * called and when post_refinement_action
     * runs.
     */
    std::vector<std::vector<bool> *> has_children;

    /**
     * A list of connections with which this object connects
     * to the triangulation to get information about when the
     * triangulation changes.
     */
    std::vector<boost::signals2::connection> tria_listeners;

    /**
     * Make accessor objects friends.
     */
    template <int, class, bool> friend class dealii::DoFAccessor;
    template <class, bool> friend class dealii::DoFCellAccessor;
    friend struct dealii::internal::DoFAccessor::Implementation;
    friend struct dealii::internal::DoFCellAccessor::Implementation;

    /**
     * Likewise for DoFLevel
     * objects since they need to
     * access the vertex dofs in
     * the functions that set and
     * retrieve vertex dof indices.
     */
    template <int> friend class dealii::internal::hp::DoFIndicesOnFacesOrEdges;
    friend struct dealii::internal::hp::DoFHandler::Implementation;
  };



#ifndef DOXYGEN


  /* ----------------------- Inline functions ---------------------------------- */

  template <int dim, int spacedim>
  inline
  types::global_dof_index
  DoFHandler<dim,spacedim>::n_dofs () const
  {
    return number_cache.n_global_dofs;
  }


  template <int dim, int spacedim>
  inline
  types::global_dof_index
  DoFHandler<dim,spacedim>::n_dofs (const unsigned int) const
  {
    return numbers::invalid_dof_index;
  }


  template <int dim, int spacedim>
  types::global_dof_index
  DoFHandler<dim, spacedim>::n_locally_owned_dofs() const
  {
    return number_cache.n_locally_owned_dofs;
  }


  template <int dim, int spacedim>
  const IndexSet &
  DoFHandler<dim, spacedim>::locally_owned_dofs() const
  {
    return number_cache.locally_owned_dofs;
  }


  template <int dim, int spacedim>
  const std::vector<types::global_dof_index> &
  DoFHandler<dim, spacedim>::n_locally_owned_dofs_per_processor() const
  {
    return number_cache.n_locally_owned_dofs_per_processor;
  }


  template <int dim, int spacedim>
  const std::vector<IndexSet> &
  DoFHandler<dim, spacedim>::locally_owned_dofs_per_processor () const
  {
    return number_cache.locally_owned_dofs_per_processor;
  }



  template<int dim, int spacedim>
  inline
  const hp::FECollection<dim,spacedim> &
  DoFHandler<dim,spacedim>::get_fe () const
  {
    Assert (finite_elements != 0,
            ExcMessage ("No finite element collection is associated with "
                        "this DoFHandler"));
    return *finite_elements;
  }


  template<int dim, int spacedim>
  inline
  const Triangulation<dim,spacedim> &
  DoFHandler<dim,spacedim>::get_tria () const
  {
    return *tria;
  }

  template<int dim, int spacedim>
  inline
  DoFHandler<dim, spacedim>::MGVertexDoFs::MGVertexDoFs()
  {
    Assert (false, ExcNotImplemented ());
  }

  template<int dim, int spacedim>
  inline
  DoFHandler<dim, spacedim>::MGVertexDoFs::~MGVertexDoFs()
  {
    Assert (false, ExcNotImplemented ());
  }

  template<int dim, int spacedim>
  inline
  types::global_dof_index DoFHandler<dim, spacedim>::MGVertexDoFs::get_index (const unsigned int,
      const unsigned int) const
  {
    Assert (false, ExcNotImplemented ());
    return invalid_dof_index;
  }

  template<int dim, int spacedim>
  inline
  void DoFHandler<dim, spacedim>::MGVertexDoFs::set_index (const unsigned int,
                                                           const unsigned int,
                                                           types::global_dof_index)
  {
    Assert (false, ExcNotImplemented ());
  }


#endif

}

DEAL_II_NAMESPACE_CLOSE

#endif