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Diffstat (limited to 'test/monniaux/glpk-4.65/src/api/prob4.c')
| -rw-r--r-- | test/monniaux/glpk-4.65/src/api/prob4.c | 156 |
1 files changed, 156 insertions, 0 deletions
diff --git a/test/monniaux/glpk-4.65/src/api/prob4.c b/test/monniaux/glpk-4.65/src/api/prob4.c new file mode 100644 index 00000000..8c2b5ae5 --- /dev/null +++ b/test/monniaux/glpk-4.65/src/api/prob4.c @@ -0,0 +1,156 @@ +/* prob4.c (problem scaling routines) */ + +/*********************************************************************** +* This code is part of GLPK (GNU Linear Programming Kit). +* +* Copyright (C) 2000-2013 Andrew Makhorin, Department for Applied +* Informatics, Moscow Aviation Institute, Moscow, Russia. All rights +* reserved. E-mail: <mao@gnu.org>. +* +* GLPK 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. +* +* GLPK 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 GLPK. If not, see <http://www.gnu.org/licenses/>. +***********************************************************************/ + +#include "env.h" +#include "prob.h" + +/*********************************************************************** +* NAME +* +* glp_set_rii - set (change) row scale factor +* +* SYNOPSIS +* +* void glp_set_rii(glp_prob *lp, int i, double rii); +* +* DESCRIPTION +* +* The routine glp_set_rii sets (changes) the scale factor r[i,i] for +* i-th row of the specified problem object. */ + +void glp_set_rii(glp_prob *lp, int i, double rii) +{ if (!(1 <= i && i <= lp->m)) + xerror("glp_set_rii: i = %d; row number out of range\n", i); + if (rii <= 0.0) + xerror("glp_set_rii: i = %d; rii = %g; invalid scale factor\n", + i, rii); + if (lp->valid && lp->row[i]->rii != rii) + { GLPAIJ *aij; + for (aij = lp->row[i]->ptr; aij != NULL; aij = aij->r_next) + { if (aij->col->stat == GLP_BS) + { /* invalidate the basis factorization */ + lp->valid = 0; + break; + } + } + } + lp->row[i]->rii = rii; + return; +} + +/*********************************************************************** +* NAME +* +* glp_set sjj - set (change) column scale factor +* +* SYNOPSIS +* +* void glp_set_sjj(glp_prob *lp, int j, double sjj); +* +* DESCRIPTION +* +* The routine glp_set_sjj sets (changes) the scale factor s[j,j] for +* j-th column of the specified problem object. */ + +void glp_set_sjj(glp_prob *lp, int j, double sjj) +{ if (!(1 <= j && j <= lp->n)) + xerror("glp_set_sjj: j = %d; column number out of range\n", j); + if (sjj <= 0.0) + xerror("glp_set_sjj: j = %d; sjj = %g; invalid scale factor\n", + j, sjj); + if (lp->valid && lp->col[j]->sjj != sjj && lp->col[j]->stat == + GLP_BS) + { /* invalidate the basis factorization */ + lp->valid = 0; + } + lp->col[j]->sjj = sjj; + return; +} + +/*********************************************************************** +* NAME +* +* glp_get_rii - retrieve row scale factor +* +* SYNOPSIS +* +* double glp_get_rii(glp_prob *lp, int i); +* +* RETURNS +* +* The routine glp_get_rii returns current scale factor r[i,i] for i-th +* row of the specified problem object. */ + +double glp_get_rii(glp_prob *lp, int i) +{ if (!(1 <= i && i <= lp->m)) + xerror("glp_get_rii: i = %d; row number out of range\n", i); + return lp->row[i]->rii; +} + +/*********************************************************************** +* NAME +* +* glp_get_sjj - retrieve column scale factor +* +* SYNOPSIS +* +* double glp_get_sjj(glp_prob *lp, int j); +* +* RETURNS +* +* The routine glp_get_sjj returns current scale factor s[j,j] for j-th +* column of the specified problem object. */ + +double glp_get_sjj(glp_prob *lp, int j) +{ if (!(1 <= j && j <= lp->n)) + xerror("glp_get_sjj: j = %d; column number out of range\n", j); + return lp->col[j]->sjj; +} + +/*********************************************************************** +* NAME +* +* glp_unscale_prob - unscale problem data +* +* SYNOPSIS +* +* void glp_unscale_prob(glp_prob *lp); +* +* DESCRIPTION +* +* The routine glp_unscale_prob performs unscaling of problem data for +* the specified problem object. +* +* "Unscaling" means replacing the current scaling matrices R and S by +* unity matrices that cancels the scaling effect. */ + +void glp_unscale_prob(glp_prob *lp) +{ int m = glp_get_num_rows(lp); + int n = glp_get_num_cols(lp); + int i, j; + for (i = 1; i <= m; i++) glp_set_rii(lp, i, 1.0); + for (j = 1; j <= n; j++) glp_set_sjj(lp, j, 1.0); + return; +} + +/* eof */ |