diff options
Diffstat (limited to 'test/monniaux/glpk-4.65/src/amd/amd_postorder.c')
| -rw-r--r-- | test/monniaux/glpk-4.65/src/amd/amd_postorder.c | 207 |
1 files changed, 207 insertions, 0 deletions
diff --git a/test/monniaux/glpk-4.65/src/amd/amd_postorder.c b/test/monniaux/glpk-4.65/src/amd/amd_postorder.c new file mode 100644 index 00000000..a3ece915 --- /dev/null +++ b/test/monniaux/glpk-4.65/src/amd/amd_postorder.c @@ -0,0 +1,207 @@ +/* ========================================================================= */ +/* === AMD_postorder ======================================================= */ +/* ========================================================================= */ + +/* ------------------------------------------------------------------------- */ +/* AMD, Copyright (c) Timothy A. Davis, */ +/* Patrick R. Amestoy, and Iain S. Duff. See ../README.txt for License. */ +/* email: davis at cise.ufl.edu CISE Department, Univ. of Florida. */ +/* web: http://www.cise.ufl.edu/research/sparse/amd */ +/* ------------------------------------------------------------------------- */ + +/* Perform a postordering (via depth-first search) of an assembly tree. */ + +#include "amd_internal.h" + +GLOBAL void AMD_postorder +( + /* inputs, not modified on output: */ + Int nn, /* nodes are in the range 0..nn-1 */ + Int Parent [ ], /* Parent [j] is the parent of j, or EMPTY if root */ + Int Nv [ ], /* Nv [j] > 0 number of pivots represented by node j, + * or zero if j is not a node. */ + Int Fsize [ ], /* Fsize [j]: size of node j */ + + /* output, not defined on input: */ + Int Order [ ], /* output post-order */ + + /* workspaces of size nn: */ + Int Child [ ], + Int Sibling [ ], + Int Stack [ ] +) +{ + Int i, j, k, parent, frsize, f, fprev, maxfrsize, bigfprev, bigf, fnext ; + + for (j = 0 ; j < nn ; j++) + { + Child [j] = EMPTY ; + Sibling [j] = EMPTY ; + } + + /* --------------------------------------------------------------------- */ + /* place the children in link lists - bigger elements tend to be last */ + /* --------------------------------------------------------------------- */ + + for (j = nn-1 ; j >= 0 ; j--) + { + if (Nv [j] > 0) + { + /* this is an element */ + parent = Parent [j] ; + if (parent != EMPTY) + { + /* place the element in link list of the children its parent */ + /* bigger elements will tend to be at the end of the list */ + Sibling [j] = Child [parent] ; + Child [parent] = j ; + } + } + } + +#ifndef NDEBUG + { + Int nels, ff, nchild ; + AMD_DEBUG1 (("\n\n================================ AMD_postorder:\n")); + nels = 0 ; + for (j = 0 ; j < nn ; j++) + { + if (Nv [j] > 0) + { + AMD_DEBUG1 (( ""ID" : nels "ID" npiv "ID" size "ID + " parent "ID" maxfr "ID"\n", j, nels, + Nv [j], Fsize [j], Parent [j], Fsize [j])) ; + /* this is an element */ + /* dump the link list of children */ + nchild = 0 ; + AMD_DEBUG1 ((" Children: ")) ; + for (ff = Child [j] ; ff != EMPTY ; ff = Sibling [ff]) + { + AMD_DEBUG1 ((ID" ", ff)) ; + ASSERT (Parent [ff] == j) ; + nchild++ ; + ASSERT (nchild < nn) ; + } + AMD_DEBUG1 (("\n")) ; + parent = Parent [j] ; + if (parent != EMPTY) + { + ASSERT (Nv [parent] > 0) ; + } + nels++ ; + } + } + } + AMD_DEBUG1 (("\n\nGo through the children of each node, and put\n" + "the biggest child last in each list:\n")) ; +#endif + + /* --------------------------------------------------------------------- */ + /* place the largest child last in the list of children for each node */ + /* --------------------------------------------------------------------- */ + + for (i = 0 ; i < nn ; i++) + { + if (Nv [i] > 0 && Child [i] != EMPTY) + { + +#ifndef NDEBUG + Int nchild ; + AMD_DEBUG1 (("Before partial sort, element "ID"\n", i)) ; + nchild = 0 ; + for (f = Child [i] ; f != EMPTY ; f = Sibling [f]) + { + ASSERT (f >= 0 && f < nn) ; + AMD_DEBUG1 ((" f: "ID" size: "ID"\n", f, Fsize [f])) ; + nchild++ ; + ASSERT (nchild <= nn) ; + } +#endif + + /* find the biggest element in the child list */ + fprev = EMPTY ; + maxfrsize = EMPTY ; + bigfprev = EMPTY ; + bigf = EMPTY ; + for (f = Child [i] ; f != EMPTY ; f = Sibling [f]) + { + ASSERT (f >= 0 && f < nn) ; + frsize = Fsize [f] ; + if (frsize >= maxfrsize) + { + /* this is the biggest seen so far */ + maxfrsize = frsize ; + bigfprev = fprev ; + bigf = f ; + } + fprev = f ; + } + ASSERT (bigf != EMPTY) ; + + fnext = Sibling [bigf] ; + + AMD_DEBUG1 (("bigf "ID" maxfrsize "ID" bigfprev "ID" fnext "ID + " fprev " ID"\n", bigf, maxfrsize, bigfprev, fnext, fprev)) ; + + if (fnext != EMPTY) + { + /* if fnext is EMPTY then bigf is already at the end of list */ + + if (bigfprev == EMPTY) + { + /* delete bigf from the element of the list */ + Child [i] = fnext ; + } + else + { + /* delete bigf from the middle of the list */ + Sibling [bigfprev] = fnext ; + } + + /* put bigf at the end of the list */ + Sibling [bigf] = EMPTY ; + ASSERT (Child [i] != EMPTY) ; + ASSERT (fprev != bigf) ; + ASSERT (fprev != EMPTY) ; + Sibling [fprev] = bigf ; + } + +#ifndef NDEBUG + AMD_DEBUG1 (("After partial sort, element "ID"\n", i)) ; + for (f = Child [i] ; f != EMPTY ; f = Sibling [f]) + { + ASSERT (f >= 0 && f < nn) ; + AMD_DEBUG1 ((" "ID" "ID"\n", f, Fsize [f])) ; + ASSERT (Nv [f] > 0) ; + nchild-- ; + } + ASSERT (nchild == 0) ; +#endif + + } + } + + /* --------------------------------------------------------------------- */ + /* postorder the assembly tree */ + /* --------------------------------------------------------------------- */ + + for (i = 0 ; i < nn ; i++) + { + Order [i] = EMPTY ; + } + + k = 0 ; + + for (i = 0 ; i < nn ; i++) + { + if (Parent [i] == EMPTY && Nv [i] > 0) + { + AMD_DEBUG1 (("Root of assembly tree "ID"\n", i)) ; + k = AMD_post_tree (i, k, Child, Sibling, Order, Stack +#ifndef NDEBUG + , nn +#endif + ) ; + } + } +} |