diff -r d59bea55db9b -r c445c931472f src/glplpx01.c --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/src/glplpx01.c Mon Dec 06 13:09:21 2010 +0100 @@ -0,0 +1,1542 @@ +/* glplpx01.c (obsolete API routines) */ + +/*********************************************************************** +* This code is part of GLPK (GNU Linear Programming Kit). +* +* Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, +* 2009, 2010 Andrew Makhorin, Department for Applied Informatics, +* Moscow Aviation Institute, Moscow, Russia. All rights reserved. +* E-mail: . +* +* 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 . +***********************************************************************/ + +#include "glpapi.h" + +struct LPXCPS +{ /* control parameters and statistics */ + int msg_lev; + /* level of messages output by the solver: + 0 - no output + 1 - error messages only + 2 - normal output + 3 - full output (includes informational messages) */ + int scale; + /* scaling option: + 0 - no scaling + 1 - equilibration scaling + 2 - geometric mean scaling + 3 - geometric mean scaling, then equilibration scaling */ + int dual; + /* dual simplex option: + 0 - use primal simplex + 1 - use dual simplex */ + int price; + /* pricing option (for both primal and dual simplex): + 0 - textbook pricing + 1 - steepest edge pricing */ + double relax; + /* relaxation parameter used in the ratio test; if it is zero, + the textbook ratio test is used; if it is non-zero (should be + positive), Harris' two-pass ratio test is used; in the latter + case on the first pass basic variables (in the case of primal + simplex) or reduced costs of non-basic variables (in the case + of dual simplex) are allowed to slightly violate their bounds, + but not more than (relax * tol_bnd) or (relax * tol_dj) (thus, + relax is a percentage of tol_bnd or tol_dj) */ + double tol_bnd; + /* relative tolerance used to check if the current basic solution + is primal feasible */ + double tol_dj; + /* absolute tolerance used to check if the current basic solution + is dual feasible */ + double tol_piv; + /* relative tolerance used to choose eligible pivotal elements of + the simplex table in the ratio test */ + int round; + /* solution rounding option: + 0 - report all computed values and reduced costs "as is" + 1 - if possible (allowed by the tolerances), replace computed + values and reduced costs which are close to zero by exact + zeros */ + double obj_ll; + /* lower limit of the objective function; if on the phase II the + objective function reaches this limit and continues decreasing, + the solver stops the search */ + double obj_ul; + /* upper limit of the objective function; if on the phase II the + objective function reaches this limit and continues increasing, + the solver stops the search */ + int it_lim; + /* simplex iterations limit; if this value is positive, it is + decreased by one each time when one simplex iteration has been + performed, and reaching zero value signals the solver to stop + the search; negative value means no iterations limit */ + double tm_lim; + /* searching time limit, in seconds; if this value is positive, + it is decreased each time when one simplex iteration has been + performed by the amount of time spent for the iteration, and + reaching zero value signals the solver to stop the search; + negative value means no time limit */ + int out_frq; + /* output frequency, in iterations; this parameter specifies how + frequently the solver sends information about the solution to + the standard output */ + double out_dly; + /* output delay, in seconds; this parameter specifies how long + the solver should delay sending information about the solution + to the standard output; zero value means no delay */ + int branch; /* MIP */ + /* branching heuristic: + 0 - branch on first variable + 1 - branch on last variable + 2 - branch using heuristic by Driebeck and Tomlin + 3 - branch on most fractional variable */ + int btrack; /* MIP */ + /* backtracking heuristic: + 0 - select most recent node (depth first search) + 1 - select earliest node (breadth first search) + 2 - select node using the best projection heuristic + 3 - select node with best local bound */ + double tol_int; /* MIP */ + /* absolute tolerance used to check if the current basic solution + is integer feasible */ + double tol_obj; /* MIP */ + /* relative tolerance used to check if the value of the objective + function is not better than in the best known integer feasible + solution */ + int mps_info; /* lpx_write_mps */ + /* if this flag is set, the routine lpx_write_mps outputs several + comment cards that contains some information about the problem; + otherwise the routine outputs no comment cards */ + int mps_obj; /* lpx_write_mps */ + /* this parameter tells the routine lpx_write_mps how to output + the objective function row: + 0 - never output objective function row + 1 - always output objective function row + 2 - output objective function row if and only if the problem + has no free rows */ + int mps_orig; /* lpx_write_mps */ + /* if this flag is set, the routine lpx_write_mps uses original + row and column symbolic names; otherwise the routine generates + plain names using ordinal numbers of rows and columns */ + int mps_wide; /* lpx_write_mps */ + /* if this flag is set, the routine lpx_write_mps uses all data + fields; otherwise the routine keeps fields 5 and 6 empty */ + int mps_free; /* lpx_write_mps */ + /* if this flag is set, the routine lpx_write_mps omits column + and vector names everytime if possible (free style); otherwise + the routine never omits these names (pedantic style) */ + int mps_skip; /* lpx_write_mps */ + /* if this flag is set, the routine lpx_write_mps skips empty + columns (i.e. which has no constraint coefficients); otherwise + the routine outputs all columns */ + int lpt_orig; /* lpx_write_lpt */ + /* if this flag is set, the routine lpx_write_lpt uses original + row and column symbolic names; otherwise the routine generates + plain names using ordinal numbers of rows and columns */ + int presol; /* lpx_simplex */ + /* LP presolver option: + 0 - do not use LP presolver + 1 - use LP presolver */ + int binarize; /* lpx_intopt */ + /* if this flag is set, the routine lpx_intopt replaces integer + columns by binary ones */ + int use_cuts; /* lpx_intopt */ + /* if this flag is set, the routine lpx_intopt tries generating + cutting planes: + LPX_C_COVER - mixed cover cuts + LPX_C_CLIQUE - clique cuts + LPX_C_GOMORY - Gomory's mixed integer cuts + LPX_C_ALL - all cuts */ + double mip_gap; /* MIP */ + /* relative MIP gap tolerance */ +}; + +LPX *lpx_create_prob(void) +{ /* create problem object */ + return glp_create_prob(); +} + +void lpx_set_prob_name(LPX *lp, const char *name) +{ /* assign (change) problem name */ + glp_set_prob_name(lp, name); + return; +} + +void lpx_set_obj_name(LPX *lp, const char *name) +{ /* assign (change) objective function name */ + glp_set_obj_name(lp, name); + return; +} + +void lpx_set_obj_dir(LPX *lp, int dir) +{ /* set (change) optimization direction flag */ + glp_set_obj_dir(lp, dir - LPX_MIN + GLP_MIN); + return; +} + +int lpx_add_rows(LPX *lp, int nrs) +{ /* add new rows to problem object */ + return glp_add_rows(lp, nrs); +} + +int lpx_add_cols(LPX *lp, int ncs) +{ /* add new columns to problem object */ + return glp_add_cols(lp, ncs); +} + +void lpx_set_row_name(LPX *lp, int i, const char *name) +{ /* assign (change) row name */ + glp_set_row_name(lp, i, name); + return; +} + +void lpx_set_col_name(LPX *lp, int j, const char *name) +{ /* assign (change) column name */ + glp_set_col_name(lp, j, name); + return; +} + +void lpx_set_row_bnds(LPX *lp, int i, int type, double lb, double ub) +{ /* set (change) row bounds */ + glp_set_row_bnds(lp, i, type - LPX_FR + GLP_FR, lb, ub); + return; +} + +void lpx_set_col_bnds(LPX *lp, int j, int type, double lb, double ub) +{ /* set (change) column bounds */ + glp_set_col_bnds(lp, j, type - LPX_FR + GLP_FR, lb, ub); + return; +} + +void lpx_set_obj_coef(glp_prob *lp, int j, double coef) +{ /* set (change) obj. coefficient or constant term */ + glp_set_obj_coef(lp, j, coef); + return; +} + +void lpx_set_mat_row(LPX *lp, int i, int len, const int ind[], + const double val[]) +{ /* set (replace) row of the constraint matrix */ + glp_set_mat_row(lp, i, len, ind, val); + return; +} + +void lpx_set_mat_col(LPX *lp, int j, int len, const int ind[], + const double val[]) +{ /* set (replace) column of the constraint matrix */ + glp_set_mat_col(lp, j, len, ind, val); + return; +} + +void lpx_load_matrix(LPX *lp, int ne, const int ia[], const int ja[], + const double ar[]) +{ /* load (replace) the whole constraint matrix */ + glp_load_matrix(lp, ne, ia, ja, ar); + return; +} + +void lpx_del_rows(LPX *lp, int nrs, const int num[]) +{ /* delete specified rows from problem object */ + glp_del_rows(lp, nrs, num); + return; +} + +void lpx_del_cols(LPX *lp, int ncs, const int num[]) +{ /* delete specified columns from problem object */ + glp_del_cols(lp, ncs, num); + return; +} + +void lpx_delete_prob(LPX *lp) +{ /* delete problem object */ + glp_delete_prob(lp); + return; +} + +const char *lpx_get_prob_name(LPX *lp) +{ /* retrieve problem name */ + return glp_get_prob_name(lp); +} + +const char *lpx_get_obj_name(LPX *lp) +{ /* retrieve objective function name */ + return glp_get_obj_name(lp); +} + +int lpx_get_obj_dir(LPX *lp) +{ /* retrieve optimization direction flag */ + return glp_get_obj_dir(lp) - GLP_MIN + LPX_MIN; +} + +int lpx_get_num_rows(LPX *lp) +{ /* retrieve number of rows */ + return glp_get_num_rows(lp); +} + +int lpx_get_num_cols(LPX *lp) +{ /* retrieve number of columns */ + return glp_get_num_cols(lp); +} + +const char *lpx_get_row_name(LPX *lp, int i) +{ /* retrieve row name */ + return glp_get_row_name(lp, i); +} + +const char *lpx_get_col_name(LPX *lp, int j) +{ /* retrieve column name */ + return glp_get_col_name(lp, j); +} + +int lpx_get_row_type(LPX *lp, int i) +{ /* retrieve row type */ + return glp_get_row_type(lp, i) - GLP_FR + LPX_FR; +} + +double lpx_get_row_lb(glp_prob *lp, int i) +{ /* retrieve row lower bound */ + double lb; + lb = glp_get_row_lb(lp, i); + if (lb == -DBL_MAX) lb = 0.0; + return lb; +} + +double lpx_get_row_ub(glp_prob *lp, int i) +{ /* retrieve row upper bound */ + double ub; + ub = glp_get_row_ub(lp, i); + if (ub == +DBL_MAX) ub = 0.0; + return ub; +} + +void lpx_get_row_bnds(glp_prob *lp, int i, int *typx, double *lb, + double *ub) +{ /* retrieve row bounds */ + if (typx != NULL) *typx = lpx_get_row_type(lp, i); + if (lb != NULL) *lb = lpx_get_row_lb(lp, i); + if (ub != NULL) *ub = lpx_get_row_ub(lp, i); + return; +} + +int lpx_get_col_type(LPX *lp, int j) +{ /* retrieve column type */ + return glp_get_col_type(lp, j) - GLP_FR + LPX_FR; +} + +double lpx_get_col_lb(glp_prob *lp, int j) +{ /* retrieve column lower bound */ + double lb; + lb = glp_get_col_lb(lp, j); + if (lb == -DBL_MAX) lb = 0.0; + return lb; +} + +double lpx_get_col_ub(glp_prob *lp, int j) +{ /* retrieve column upper bound */ + double ub; + ub = glp_get_col_ub(lp, j); + if (ub == +DBL_MAX) ub = 0.0; + return ub; +} + +void lpx_get_col_bnds(glp_prob *lp, int j, int *typx, double *lb, + double *ub) +{ /* retrieve column bounds */ + if (typx != NULL) *typx = lpx_get_col_type(lp, j); + if (lb != NULL) *lb = lpx_get_col_lb(lp, j); + if (ub != NULL) *ub = lpx_get_col_ub(lp, j); + return; +} + +double lpx_get_obj_coef(LPX *lp, int j) +{ /* retrieve obj. coefficient or constant term */ + return glp_get_obj_coef(lp, j); +} + +int lpx_get_num_nz(LPX *lp) +{ /* retrieve number of constraint coefficients */ + return glp_get_num_nz(lp); +} + +int lpx_get_mat_row(LPX *lp, int i, int ind[], double val[]) +{ /* retrieve row of the constraint matrix */ + return glp_get_mat_row(lp, i, ind, val); +} + +int lpx_get_mat_col(LPX *lp, int j, int ind[], double val[]) +{ /* retrieve column of the constraint matrix */ + return glp_get_mat_col(lp, j, ind, val); +} + +void lpx_create_index(LPX *lp) +{ /* create the name index */ + glp_create_index(lp); + return; +} + +int lpx_find_row(LPX *lp, const char *name) +{ /* find row by its name */ + return glp_find_row(lp, name); +} + +int lpx_find_col(LPX *lp, const char *name) +{ /* find column by its name */ + return glp_find_col(lp, name); +} + +void lpx_delete_index(LPX *lp) +{ /* delete the name index */ + glp_delete_index(lp); + return; +} + +void lpx_scale_prob(LPX *lp) +{ /* scale problem data */ + switch (lpx_get_int_parm(lp, LPX_K_SCALE)) + { case 0: + /* no scaling */ + glp_unscale_prob(lp); + break; + case 1: + /* equilibration scaling */ + glp_scale_prob(lp, GLP_SF_EQ); + break; + case 2: + /* geometric mean scaling */ + glp_scale_prob(lp, GLP_SF_GM); + break; + case 3: + /* geometric mean scaling, then equilibration scaling */ + glp_scale_prob(lp, GLP_SF_GM | GLP_SF_EQ); + break; + default: + xassert(lp != lp); + } + return; +} + +void lpx_unscale_prob(LPX *lp) +{ /* unscale problem data */ + glp_unscale_prob(lp); + return; +} + +void lpx_set_row_stat(LPX *lp, int i, int stat) +{ /* set (change) row status */ + glp_set_row_stat(lp, i, stat - LPX_BS + GLP_BS); + return; +} + +void lpx_set_col_stat(LPX *lp, int j, int stat) +{ /* set (change) column status */ + glp_set_col_stat(lp, j, stat - LPX_BS + GLP_BS); + return; +} + +void lpx_std_basis(LPX *lp) +{ /* construct standard initial LP basis */ + glp_std_basis(lp); + return; +} + +void lpx_adv_basis(LPX *lp) +{ /* construct advanced initial LP basis */ + glp_adv_basis(lp, 0); + return; +} + +void lpx_cpx_basis(LPX *lp) +{ /* construct Bixby's initial LP basis */ + glp_cpx_basis(lp); + return; +} + +static void fill_smcp(LPX *lp, glp_smcp *parm) +{ glp_init_smcp(parm); + switch (lpx_get_int_parm(lp, LPX_K_MSGLEV)) + { case 0: parm->msg_lev = GLP_MSG_OFF; break; + case 1: parm->msg_lev = GLP_MSG_ERR; break; + case 2: parm->msg_lev = GLP_MSG_ON; break; + case 3: parm->msg_lev = GLP_MSG_ALL; break; + default: xassert(lp != lp); + } + switch (lpx_get_int_parm(lp, LPX_K_DUAL)) + { case 0: parm->meth = GLP_PRIMAL; break; + case 1: parm->meth = GLP_DUAL; break; + default: xassert(lp != lp); + } + switch (lpx_get_int_parm(lp, LPX_K_PRICE)) + { case 0: parm->pricing = GLP_PT_STD; break; + case 1: parm->pricing = GLP_PT_PSE; break; + default: xassert(lp != lp); + } + if (lpx_get_real_parm(lp, LPX_K_RELAX) == 0.0) + parm->r_test = GLP_RT_STD; + else + parm->r_test = GLP_RT_HAR; + parm->tol_bnd = lpx_get_real_parm(lp, LPX_K_TOLBND); + parm->tol_dj = lpx_get_real_parm(lp, LPX_K_TOLDJ); + parm->tol_piv = lpx_get_real_parm(lp, LPX_K_TOLPIV); + parm->obj_ll = lpx_get_real_parm(lp, LPX_K_OBJLL); + parm->obj_ul = lpx_get_real_parm(lp, LPX_K_OBJUL); + if (lpx_get_int_parm(lp, LPX_K_ITLIM) < 0) + parm->it_lim = INT_MAX; + else + parm->it_lim = lpx_get_int_parm(lp, LPX_K_ITLIM); + if (lpx_get_real_parm(lp, LPX_K_TMLIM) < 0.0) + parm->tm_lim = INT_MAX; + else + parm->tm_lim = + (int)(1000.0 * lpx_get_real_parm(lp, LPX_K_TMLIM)); + parm->out_frq = lpx_get_int_parm(lp, LPX_K_OUTFRQ); + parm->out_dly = + (int)(1000.0 * lpx_get_real_parm(lp, LPX_K_OUTDLY)); + switch (lpx_get_int_parm(lp, LPX_K_PRESOL)) + { case 0: parm->presolve = GLP_OFF; break; + case 1: parm->presolve = GLP_ON; break; + default: xassert(lp != lp); + } + return; +} + +int lpx_simplex(LPX *lp) +{ /* easy-to-use driver to the simplex method */ + glp_smcp parm; + int ret; + fill_smcp(lp, &parm); + ret = glp_simplex(lp, &parm); + switch (ret) + { case 0: ret = LPX_E_OK; break; + case GLP_EBADB: + case GLP_ESING: + case GLP_ECOND: + case GLP_EBOUND: ret = LPX_E_FAULT; break; + case GLP_EFAIL: ret = LPX_E_SING; break; + case GLP_EOBJLL: ret = LPX_E_OBJLL; break; + case GLP_EOBJUL: ret = LPX_E_OBJUL; break; + case GLP_EITLIM: ret = LPX_E_ITLIM; break; + case GLP_ETMLIM: ret = LPX_E_TMLIM; break; + case GLP_ENOPFS: ret = LPX_E_NOPFS; break; + case GLP_ENODFS: ret = LPX_E_NODFS; break; + default: xassert(ret != ret); + } + return ret; +} + +int lpx_exact(LPX *lp) +{ /* easy-to-use driver to the exact simplex method */ + glp_smcp parm; + int ret; + fill_smcp(lp, &parm); + ret = glp_exact(lp, &parm); + switch (ret) + { case 0: ret = LPX_E_OK; break; + case GLP_EBADB: + case GLP_ESING: + case GLP_EBOUND: + case GLP_EFAIL: ret = LPX_E_FAULT; break; + case GLP_EITLIM: ret = LPX_E_ITLIM; break; + case GLP_ETMLIM: ret = LPX_E_TMLIM; break; + default: xassert(ret != ret); + } + return ret; +} + +int lpx_get_status(glp_prob *lp) +{ /* retrieve generic status of basic solution */ + int status; + switch (glp_get_status(lp)) + { case GLP_OPT: status = LPX_OPT; break; + case GLP_FEAS: status = LPX_FEAS; break; + case GLP_INFEAS: status = LPX_INFEAS; break; + case GLP_NOFEAS: status = LPX_NOFEAS; break; + case GLP_UNBND: status = LPX_UNBND; break; + case GLP_UNDEF: status = LPX_UNDEF; break; + default: xassert(lp != lp); + } + return status; +} + +int lpx_get_prim_stat(glp_prob *lp) +{ /* retrieve status of primal basic solution */ + return glp_get_prim_stat(lp) - GLP_UNDEF + LPX_P_UNDEF; +} + +int lpx_get_dual_stat(glp_prob *lp) +{ /* retrieve status of dual basic solution */ + return glp_get_dual_stat(lp) - GLP_UNDEF + LPX_D_UNDEF; +} + +double lpx_get_obj_val(LPX *lp) +{ /* retrieve objective value (basic solution) */ + return glp_get_obj_val(lp); +} + +int lpx_get_row_stat(LPX *lp, int i) +{ /* retrieve row status (basic solution) */ + return glp_get_row_stat(lp, i) - GLP_BS + LPX_BS; +} + +double lpx_get_row_prim(LPX *lp, int i) +{ /* retrieve row primal value (basic solution) */ + return glp_get_row_prim(lp, i); +} + +double lpx_get_row_dual(LPX *lp, int i) +{ /* retrieve row dual value (basic solution) */ + return glp_get_row_dual(lp, i); +} + +void lpx_get_row_info(glp_prob *lp, int i, int *tagx, double *vx, + double *dx) +{ /* obtain row solution information */ + if (tagx != NULL) *tagx = lpx_get_row_stat(lp, i); + if (vx != NULL) *vx = lpx_get_row_prim(lp, i); + if (dx != NULL) *dx = lpx_get_row_dual(lp, i); + return; +} + +int lpx_get_col_stat(LPX *lp, int j) +{ /* retrieve column status (basic solution) */ + return glp_get_col_stat(lp, j) - GLP_BS + LPX_BS; +} + +double lpx_get_col_prim(LPX *lp, int j) +{ /* retrieve column primal value (basic solution) */ + return glp_get_col_prim(lp, j); +} + +double lpx_get_col_dual(glp_prob *lp, int j) +{ /* retrieve column dual value (basic solution) */ + return glp_get_col_dual(lp, j); +} + +void lpx_get_col_info(glp_prob *lp, int j, int *tagx, double *vx, + double *dx) +{ /* obtain column solution information */ + if (tagx != NULL) *tagx = lpx_get_col_stat(lp, j); + if (vx != NULL) *vx = lpx_get_col_prim(lp, j); + if (dx != NULL) *dx = lpx_get_col_dual(lp, j); + return; +} + +int lpx_get_ray_info(LPX *lp) +{ /* determine what causes primal unboundness */ + return glp_get_unbnd_ray(lp); +} + +void lpx_check_kkt(LPX *lp, int scaled, LPXKKT *kkt) +{ /* check Karush-Kuhn-Tucker conditions */ + int ae_ind, re_ind; + double ae_max, re_max; + xassert(scaled == scaled); + _glp_check_kkt(lp, GLP_SOL, GLP_KKT_PE, &ae_max, &ae_ind, &re_max, + &re_ind); + kkt->pe_ae_max = ae_max; + kkt->pe_ae_row = ae_ind; + kkt->pe_re_max = re_max; + kkt->pe_re_row = re_ind; + if (re_max <= 1e-9) + kkt->pe_quality = 'H'; + else if (re_max <= 1e-6) + kkt->pe_quality = 'M'; + else if (re_max <= 1e-3) + kkt->pe_quality = 'L'; + else + kkt->pe_quality = '?'; + _glp_check_kkt(lp, GLP_SOL, GLP_KKT_PB, &ae_max, &ae_ind, &re_max, + &re_ind); + kkt->pb_ae_max = ae_max; + kkt->pb_ae_ind = ae_ind; + kkt->pb_re_max = re_max; + kkt->pb_re_ind = re_ind; + if (re_max <= 1e-9) + kkt->pb_quality = 'H'; + else if (re_max <= 1e-6) + kkt->pb_quality = 'M'; + else if (re_max <= 1e-3) + kkt->pb_quality = 'L'; + else + kkt->pb_quality = '?'; + _glp_check_kkt(lp, GLP_SOL, GLP_KKT_DE, &ae_max, &ae_ind, &re_max, + &re_ind); + kkt->de_ae_max = ae_max; + if (ae_ind == 0) + kkt->de_ae_col = 0; + else + kkt->de_ae_col = ae_ind - lp->m; + kkt->de_re_max = re_max; + if (re_ind == 0) + kkt->de_re_col = 0; + else + kkt->de_re_col = ae_ind - lp->m; + if (re_max <= 1e-9) + kkt->de_quality = 'H'; + else if (re_max <= 1e-6) + kkt->de_quality = 'M'; + else if (re_max <= 1e-3) + kkt->de_quality = 'L'; + else + kkt->de_quality = '?'; + _glp_check_kkt(lp, GLP_SOL, GLP_KKT_DB, &ae_max, &ae_ind, &re_max, + &re_ind); + kkt->db_ae_max = ae_max; + kkt->db_ae_ind = ae_ind; + kkt->db_re_max = re_max; + kkt->db_re_ind = re_ind; + if (re_max <= 1e-9) + kkt->db_quality = 'H'; + else if (re_max <= 1e-6) + kkt->db_quality = 'M'; + else if (re_max <= 1e-3) + kkt->db_quality = 'L'; + else + kkt->db_quality = '?'; + kkt->cs_ae_max = 0.0, kkt->cs_ae_ind = 0; + kkt->cs_re_max = 0.0, kkt->cs_re_ind = 0; + kkt->cs_quality = 'H'; + return; +} + +int lpx_warm_up(LPX *lp) +{ /* "warm up" LP basis */ + int ret; + ret = glp_warm_up(lp); + if (ret == 0) + ret = LPX_E_OK; + else if (ret == GLP_EBADB) + ret = LPX_E_BADB; + else if (ret == GLP_ESING) + ret = LPX_E_SING; + else if (ret == GLP_ECOND) + ret = LPX_E_SING; + else + xassert(ret != ret); + return ret; +} + +int lpx_eval_tab_row(LPX *lp, int k, int ind[], double val[]) +{ /* compute row of the simplex tableau */ + return glp_eval_tab_row(lp, k, ind, val); +} + +int lpx_eval_tab_col(LPX *lp, int k, int ind[], double val[]) +{ /* compute column of the simplex tableau */ + return glp_eval_tab_col(lp, k, ind, val); +} + +int lpx_transform_row(LPX *lp, int len, int ind[], double val[]) +{ /* transform explicitly specified row */ + return glp_transform_row(lp, len, ind, val); +} + +int lpx_transform_col(LPX *lp, int len, int ind[], double val[]) +{ /* transform explicitly specified column */ + return glp_transform_col(lp, len, ind, val); +} + +int lpx_prim_ratio_test(LPX *lp, int len, const int ind[], + const double val[], int how, double tol) +{ /* perform primal ratio test */ + int piv; + piv = glp_prim_rtest(lp, len, ind, val, how, tol); + xassert(0 <= piv && piv <= len); + return piv == 0 ? 0 : ind[piv]; +} + +int lpx_dual_ratio_test(LPX *lp, int len, const int ind[], + const double val[], int how, double tol) +{ /* perform dual ratio test */ + int piv; + piv = glp_dual_rtest(lp, len, ind, val, how, tol); + xassert(0 <= piv && piv <= len); + return piv == 0 ? 0 : ind[piv]; +} + +int lpx_interior(LPX *lp) +{ /* easy-to-use driver to the interior-point method */ + int ret; + ret = glp_interior(lp, NULL); + switch (ret) + { case 0: ret = LPX_E_OK; break; + case GLP_EFAIL: ret = LPX_E_FAULT; break; + case GLP_ENOFEAS: ret = LPX_E_NOFEAS; break; + case GLP_ENOCVG: ret = LPX_E_NOCONV; break; + case GLP_EITLIM: ret = LPX_E_ITLIM; break; + case GLP_EINSTAB: ret = LPX_E_INSTAB; break; + default: xassert(ret != ret); + } + return ret; +} + +int lpx_ipt_status(glp_prob *lp) +{ /* retrieve status of interior-point solution */ + int status; + switch (glp_ipt_status(lp)) + { case GLP_UNDEF: status = LPX_T_UNDEF; break; + case GLP_OPT: status = LPX_T_OPT; break; + default: xassert(lp != lp); + } + return status; +} + +double lpx_ipt_obj_val(LPX *lp) +{ /* retrieve objective value (interior point) */ + return glp_ipt_obj_val(lp); +} + +double lpx_ipt_row_prim(LPX *lp, int i) +{ /* retrieve row primal value (interior point) */ + return glp_ipt_row_prim(lp, i); +} + +double lpx_ipt_row_dual(LPX *lp, int i) +{ /* retrieve row dual value (interior point) */ + return glp_ipt_row_dual(lp, i); +} + +double lpx_ipt_col_prim(LPX *lp, int j) +{ /* retrieve column primal value (interior point) */ + return glp_ipt_col_prim(lp, j); +} + +double lpx_ipt_col_dual(LPX *lp, int j) +{ /* retrieve column dual value (interior point) */ + return glp_ipt_col_dual(lp, j); +} + +void lpx_set_class(LPX *lp, int klass) +{ /* set problem class */ + xassert(lp == lp); + if (!(klass == LPX_LP || klass == LPX_MIP)) + xerror("lpx_set_class: invalid problem class\n"); + return; +} + +int lpx_get_class(LPX *lp) +{ /* determine problem klass */ + return glp_get_num_int(lp) == 0 ? LPX_LP : LPX_MIP; +} + +void lpx_set_col_kind(LPX *lp, int j, int kind) +{ /* set (change) column kind */ + glp_set_col_kind(lp, j, kind - LPX_CV + GLP_CV); + return; +} + +int lpx_get_col_kind(LPX *lp, int j) +{ /* retrieve column kind */ + return glp_get_col_kind(lp, j) == GLP_CV ? LPX_CV : LPX_IV; +} + +int lpx_get_num_int(LPX *lp) +{ /* retrieve number of integer columns */ + return glp_get_num_int(lp); +} + +int lpx_get_num_bin(LPX *lp) +{ /* retrieve number of binary columns */ + return glp_get_num_bin(lp); +} + +static int solve_mip(LPX *lp, int presolve) +{ glp_iocp parm; + int ret; + glp_init_iocp(&parm); + switch (lpx_get_int_parm(lp, LPX_K_MSGLEV)) + { case 0: parm.msg_lev = GLP_MSG_OFF; break; + case 1: parm.msg_lev = GLP_MSG_ERR; break; + case 2: parm.msg_lev = GLP_MSG_ON; break; + case 3: parm.msg_lev = GLP_MSG_ALL; break; + default: xassert(lp != lp); + } + switch (lpx_get_int_parm(lp, LPX_K_BRANCH)) + { case 0: parm.br_tech = GLP_BR_FFV; break; + case 1: parm.br_tech = GLP_BR_LFV; break; + case 2: parm.br_tech = GLP_BR_DTH; break; + case 3: parm.br_tech = GLP_BR_MFV; break; + default: xassert(lp != lp); + } + switch (lpx_get_int_parm(lp, LPX_K_BTRACK)) + { case 0: parm.bt_tech = GLP_BT_DFS; break; + case 1: parm.bt_tech = GLP_BT_BFS; break; + case 2: parm.bt_tech = GLP_BT_BPH; break; + case 3: parm.bt_tech = GLP_BT_BLB; break; + default: xassert(lp != lp); + } + parm.tol_int = lpx_get_real_parm(lp, LPX_K_TOLINT); + parm.tol_obj = lpx_get_real_parm(lp, LPX_K_TOLOBJ); + if (lpx_get_real_parm(lp, LPX_K_TMLIM) < 0.0 || + lpx_get_real_parm(lp, LPX_K_TMLIM) > 1e6) + parm.tm_lim = INT_MAX; + else + parm.tm_lim = + (int)(1000.0 * lpx_get_real_parm(lp, LPX_K_TMLIM)); + parm.mip_gap = lpx_get_real_parm(lp, LPX_K_MIPGAP); + if (lpx_get_int_parm(lp, LPX_K_USECUTS) & LPX_C_GOMORY) + parm.gmi_cuts = GLP_ON; + else + parm.gmi_cuts = GLP_OFF; + if (lpx_get_int_parm(lp, LPX_K_USECUTS) & LPX_C_MIR) + parm.mir_cuts = GLP_ON; + else + parm.mir_cuts = GLP_OFF; + if (lpx_get_int_parm(lp, LPX_K_USECUTS) & LPX_C_COVER) + parm.cov_cuts = GLP_ON; + else + parm.cov_cuts = GLP_OFF; + if (lpx_get_int_parm(lp, LPX_K_USECUTS) & LPX_C_CLIQUE) + parm.clq_cuts = GLP_ON; + else + parm.clq_cuts = GLP_OFF; + parm.presolve = presolve; + if (lpx_get_int_parm(lp, LPX_K_BINARIZE)) + parm.binarize = GLP_ON; + ret = glp_intopt(lp, &parm); + switch (ret) + { case 0: ret = LPX_E_OK; break; + case GLP_ENOPFS: ret = LPX_E_NOPFS; break; + case GLP_ENODFS: ret = LPX_E_NODFS; break; + case GLP_EBOUND: + case GLP_EROOT: ret = LPX_E_FAULT; break; + case GLP_EFAIL: ret = LPX_E_SING; break; + case GLP_EMIPGAP: ret = LPX_E_MIPGAP; break; + case GLP_ETMLIM: ret = LPX_E_TMLIM; break; + default: xassert(ret != ret); + } + return ret; +} + +int lpx_integer(LPX *lp) +{ /* easy-to-use driver to the branch-and-bound method */ + return solve_mip(lp, GLP_OFF); +} + +int lpx_intopt(LPX *lp) +{ /* easy-to-use driver to the branch-and-bound method */ + return solve_mip(lp, GLP_ON); +} + +int lpx_mip_status(glp_prob *lp) +{ /* retrieve status of MIP solution */ + int status; + switch (glp_mip_status(lp)) + { case GLP_UNDEF: status = LPX_I_UNDEF; break; + case GLP_OPT: status = LPX_I_OPT; break; + case GLP_FEAS: status = LPX_I_FEAS; break; + case GLP_NOFEAS: status = LPX_I_NOFEAS; break; + default: xassert(lp != lp); + } + return status; +} + +double lpx_mip_obj_val(LPX *lp) +{ /* retrieve objective value (MIP solution) */ + return glp_mip_obj_val(lp); +} + +double lpx_mip_row_val(LPX *lp, int i) +{ /* retrieve row value (MIP solution) */ + return glp_mip_row_val(lp, i); +} + +double lpx_mip_col_val(LPX *lp, int j) +{ /* retrieve column value (MIP solution) */ + return glp_mip_col_val(lp, j); +} + +void lpx_check_int(LPX *lp, LPXKKT *kkt) +{ /* check integer feasibility conditions */ + int ae_ind, re_ind; + double ae_max, re_max; + _glp_check_kkt(lp, GLP_MIP, GLP_KKT_PE, &ae_max, &ae_ind, &re_max, + &re_ind); + kkt->pe_ae_max = ae_max; + kkt->pe_ae_row = ae_ind; + kkt->pe_re_max = re_max; + kkt->pe_re_row = re_ind; + if (re_max <= 1e-9) + kkt->pe_quality = 'H'; + else if (re_max <= 1e-6) + kkt->pe_quality = 'M'; + else if (re_max <= 1e-3) + kkt->pe_quality = 'L'; + else + kkt->pe_quality = '?'; + _glp_check_kkt(lp, GLP_MIP, GLP_KKT_PB, &ae_max, &ae_ind, &re_max, + &re_ind); + kkt->pb_ae_max = ae_max; + kkt->pb_ae_ind = ae_ind; + kkt->pb_re_max = re_max; + kkt->pb_re_ind = re_ind; + if (re_max <= 1e-9) + kkt->pb_quality = 'H'; + else if (re_max <= 1e-6) + kkt->pb_quality = 'M'; + else if (re_max <= 1e-3) + kkt->pb_quality = 'L'; + else + kkt->pb_quality = '?'; + return; +} + +#if 1 /* 17/XI-2009 */ +static void reset_parms(LPX *lp) +{ /* reset control parameters to default values */ + struct LPXCPS *cps = lp->parms; + xassert(cps != NULL); + cps->msg_lev = 3; + cps->scale = 1; + cps->dual = 0; + cps->price = 1; + cps->relax = 0.07; + cps->tol_bnd = 1e-7; + cps->tol_dj = 1e-7; + cps->tol_piv = 1e-9; + cps->round = 0; + cps->obj_ll = -DBL_MAX; + cps->obj_ul = +DBL_MAX; + cps->it_lim = -1; +#if 0 /* 02/XII-2010 */ + lp->it_cnt = 0; +#endif + cps->tm_lim = -1.0; + cps->out_frq = 200; + cps->out_dly = 0.0; + cps->branch = 2; + cps->btrack = 3; + cps->tol_int = 1e-5; + cps->tol_obj = 1e-7; + cps->mps_info = 1; + cps->mps_obj = 2; + cps->mps_orig = 0; + cps->mps_wide = 1; + cps->mps_free = 0; + cps->mps_skip = 0; + cps->lpt_orig = 0; + cps->presol = 0; + cps->binarize = 0; + cps->use_cuts = 0; + cps->mip_gap = 0.0; + return; +} +#endif + +#if 1 /* 17/XI-2009 */ +static struct LPXCPS *access_parms(LPX *lp) +{ /* allocate and initialize control parameters, if necessary */ + if (lp->parms == NULL) + { lp->parms = xmalloc(sizeof(struct LPXCPS)); + reset_parms(lp); + } + return lp->parms; +} +#endif + +#if 1 /* 17/XI-2009 */ +void lpx_reset_parms(LPX *lp) +{ /* reset control parameters to default values */ + access_parms(lp); + reset_parms(lp); + return; +} +#endif + +void lpx_set_int_parm(LPX *lp, int parm, int val) +{ /* set (change) integer control parameter */ +#if 0 /* 17/XI-2009 */ + struct LPXCPS *cps = lp->cps; +#else + struct LPXCPS *cps = access_parms(lp); +#endif + switch (parm) + { case LPX_K_MSGLEV: + if (!(0 <= val && val <= 3)) + xerror("lpx_set_int_parm: MSGLEV = %d; invalid value\n", + val); + cps->msg_lev = val; + break; + case LPX_K_SCALE: + if (!(0 <= val && val <= 3)) + xerror("lpx_set_int_parm: SCALE = %d; invalid value\n", + val); + cps->scale = val; + break; + case LPX_K_DUAL: + if (!(val == 0 || val == 1)) + xerror("lpx_set_int_parm: DUAL = %d; invalid value\n", + val); + cps->dual = val; + break; + case LPX_K_PRICE: + if (!(val == 0 || val == 1)) + xerror("lpx_set_int_parm: PRICE = %d; invalid value\n", + val); + cps->price = val; + break; + case LPX_K_ROUND: + if (!(val == 0 || val == 1)) + xerror("lpx_set_int_parm: ROUND = %d; invalid value\n", + val); + cps->round = val; + break; + case LPX_K_ITLIM: + cps->it_lim = val; + break; + case LPX_K_ITCNT: + lp->it_cnt = val; + break; + case LPX_K_OUTFRQ: + if (!(val > 0)) + xerror("lpx_set_int_parm: OUTFRQ = %d; invalid value\n", + val); + cps->out_frq = val; + break; + case LPX_K_BRANCH: + if (!(val == 0 || val == 1 || val == 2 || val == 3)) + xerror("lpx_set_int_parm: BRANCH = %d; invalid value\n", + val); + cps->branch = val; + break; + case LPX_K_BTRACK: + if (!(val == 0 || val == 1 || val == 2 || val == 3)) + xerror("lpx_set_int_parm: BTRACK = %d; invalid value\n", + val); + cps->btrack = val; + break; + case LPX_K_MPSINFO: + if (!(val == 0 || val == 1)) + xerror("lpx_set_int_parm: MPSINFO = %d; invalid value\n", + val); + cps->mps_info = val; + break; + case LPX_K_MPSOBJ: + if (!(val == 0 || val == 1 || val == 2)) + xerror("lpx_set_int_parm: MPSOBJ = %d; invalid value\n", + val); + cps->mps_obj = val; + break; + case LPX_K_MPSORIG: + if (!(val == 0 || val == 1)) + xerror("lpx_set_int_parm: MPSORIG = %d; invalid value\n", + val); + cps->mps_orig = val; + break; + case LPX_K_MPSWIDE: + if (!(val == 0 || val == 1)) + xerror("lpx_set_int_parm: MPSWIDE = %d; invalid value\n", + val); + cps->mps_wide = val; + break; + case LPX_K_MPSFREE: + if (!(val == 0 || val == 1)) + xerror("lpx_set_int_parm: MPSFREE = %d; invalid value\n", + val); + cps->mps_free = val; + break; + case LPX_K_MPSSKIP: + if (!(val == 0 || val == 1)) + xerror("lpx_set_int_parm: MPSSKIP = %d; invalid value\n", + val); + cps->mps_skip = val; + break; + case LPX_K_LPTORIG: + if (!(val == 0 || val == 1)) + xerror("lpx_set_int_parm: LPTORIG = %d; invalid value\n", + val); + cps->lpt_orig = val; + break; + case LPX_K_PRESOL: + if (!(val == 0 || val == 1)) + xerror("lpx_set_int_parm: PRESOL = %d; invalid value\n", + val); + cps->presol = val; + break; + case LPX_K_BINARIZE: + if (!(val == 0 || val == 1)) + xerror("lpx_set_int_parm: BINARIZE = %d; invalid value\n" + , val); + cps->binarize = val; + break; + case LPX_K_USECUTS: + if (val & ~LPX_C_ALL) + xerror("lpx_set_int_parm: USECUTS = 0x%X; invalid value\n", + val); + cps->use_cuts = val; + break; + case LPX_K_BFTYPE: +#if 0 + if (!(1 <= val && val <= 3)) + xerror("lpx_set_int_parm: BFTYPE = %d; invalid value\n", + val); + cps->bf_type = val; +#else + { glp_bfcp parm; + glp_get_bfcp(lp, &parm); + switch (val) + { case 1: + parm.type = GLP_BF_FT; break; + case 2: + parm.type = GLP_BF_BG; break; + case 3: + parm.type = GLP_BF_GR; break; + default: + xerror("lpx_set_int_parm: BFTYPE = %d; invalid val" + "ue\n", val); + } + glp_set_bfcp(lp, &parm); + } +#endif + break; + default: + xerror("lpx_set_int_parm: parm = %d; invalid parameter\n", + parm); + } + return; +} + +int lpx_get_int_parm(LPX *lp, int parm) +{ /* query integer control parameter */ +#if 0 /* 17/XI-2009 */ + struct LPXCPS *cps = lp->cps; +#else + struct LPXCPS *cps = access_parms(lp); +#endif + int val = 0; + switch (parm) + { case LPX_K_MSGLEV: + val = cps->msg_lev; break; + case LPX_K_SCALE: + val = cps->scale; break; + case LPX_K_DUAL: + val = cps->dual; break; + case LPX_K_PRICE: + val = cps->price; break; + case LPX_K_ROUND: + val = cps->round; break; + case LPX_K_ITLIM: + val = cps->it_lim; break; + case LPX_K_ITCNT: + val = lp->it_cnt; break; + case LPX_K_OUTFRQ: + val = cps->out_frq; break; + case LPX_K_BRANCH: + val = cps->branch; break; + case LPX_K_BTRACK: + val = cps->btrack; break; + case LPX_K_MPSINFO: + val = cps->mps_info; break; + case LPX_K_MPSOBJ: + val = cps->mps_obj; break; + case LPX_K_MPSORIG: + val = cps->mps_orig; break; + case LPX_K_MPSWIDE: + val = cps->mps_wide; break; + case LPX_K_MPSFREE: + val = cps->mps_free; break; + case LPX_K_MPSSKIP: + val = cps->mps_skip; break; + case LPX_K_LPTORIG: + val = cps->lpt_orig; break; + case LPX_K_PRESOL: + val = cps->presol; break; + case LPX_K_BINARIZE: + val = cps->binarize; break; + case LPX_K_USECUTS: + val = cps->use_cuts; break; + case LPX_K_BFTYPE: +#if 0 + val = cps->bf_type; break; +#else + { glp_bfcp parm; + glp_get_bfcp(lp, &parm); + switch (parm.type) + { case GLP_BF_FT: + val = 1; break; + case GLP_BF_BG: + val = 2; break; + case GLP_BF_GR: + val = 3; break; + default: + xassert(lp != lp); + } + } + break; +#endif + default: + xerror("lpx_get_int_parm: parm = %d; invalid parameter\n", + parm); + } + return val; +} + +void lpx_set_real_parm(LPX *lp, int parm, double val) +{ /* set (change) real control parameter */ +#if 0 /* 17/XI-2009 */ + struct LPXCPS *cps = lp->cps; +#else + struct LPXCPS *cps = access_parms(lp); +#endif + switch (parm) + { case LPX_K_RELAX: + if (!(0.0 <= val && val <= 1.0)) + xerror("lpx_set_real_parm: RELAX = %g; invalid value\n", + val); + cps->relax = val; + break; + case LPX_K_TOLBND: + if (!(DBL_EPSILON <= val && val <= 0.001)) + xerror("lpx_set_real_parm: TOLBND = %g; invalid value\n", + val); +#if 0 + if (cps->tol_bnd > val) + { /* invalidate the basic solution */ + lp->p_stat = LPX_P_UNDEF; + lp->d_stat = LPX_D_UNDEF; + } +#endif + cps->tol_bnd = val; + break; + case LPX_K_TOLDJ: + if (!(DBL_EPSILON <= val && val <= 0.001)) + xerror("lpx_set_real_parm: TOLDJ = %g; invalid value\n", + val); +#if 0 + if (cps->tol_dj > val) + { /* invalidate the basic solution */ + lp->p_stat = LPX_P_UNDEF; + lp->d_stat = LPX_D_UNDEF; + } +#endif + cps->tol_dj = val; + break; + case LPX_K_TOLPIV: + if (!(DBL_EPSILON <= val && val <= 0.001)) + xerror("lpx_set_real_parm: TOLPIV = %g; invalid value\n", + val); + cps->tol_piv = val; + break; + case LPX_K_OBJLL: + cps->obj_ll = val; + break; + case LPX_K_OBJUL: + cps->obj_ul = val; + break; + case LPX_K_TMLIM: + cps->tm_lim = val; + break; + case LPX_K_OUTDLY: + cps->out_dly = val; + break; + case LPX_K_TOLINT: + if (!(DBL_EPSILON <= val && val <= 0.001)) + xerror("lpx_set_real_parm: TOLINT = %g; invalid value\n", + val); + cps->tol_int = val; + break; + case LPX_K_TOLOBJ: + if (!(DBL_EPSILON <= val && val <= 0.001)) + xerror("lpx_set_real_parm: TOLOBJ = %g; invalid value\n", + val); + cps->tol_obj = val; + break; + case LPX_K_MIPGAP: + if (val < 0.0) + xerror("lpx_set_real_parm: MIPGAP = %g; invalid value\n", + val); + cps->mip_gap = val; + break; + default: + xerror("lpx_set_real_parm: parm = %d; invalid parameter\n", + parm); + } + return; +} + +double lpx_get_real_parm(LPX *lp, int parm) +{ /* query real control parameter */ +#if 0 /* 17/XI-2009 */ + struct LPXCPS *cps = lp->cps; +#else + struct LPXCPS *cps = access_parms(lp); +#endif + double val = 0.0; + switch (parm) + { case LPX_K_RELAX: + val = cps->relax; + break; + case LPX_K_TOLBND: + val = cps->tol_bnd; + break; + case LPX_K_TOLDJ: + val = cps->tol_dj; + break; + case LPX_K_TOLPIV: + val = cps->tol_piv; + break; + case LPX_K_OBJLL: + val = cps->obj_ll; + break; + case LPX_K_OBJUL: + val = cps->obj_ul; + break; + case LPX_K_TMLIM: + val = cps->tm_lim; + break; + case LPX_K_OUTDLY: + val = cps->out_dly; + break; + case LPX_K_TOLINT: + val = cps->tol_int; + break; + case LPX_K_TOLOBJ: + val = cps->tol_obj; + break; + case LPX_K_MIPGAP: + val = cps->mip_gap; + break; + default: + xerror("lpx_get_real_parm: parm = %d; invalid parameter\n", + parm); + } + return val; +} + +LPX *lpx_read_mps(const char *fname) +{ /* read problem data in fixed MPS format */ + LPX *lp = lpx_create_prob(); + if (glp_read_mps(lp, GLP_MPS_DECK, NULL, fname)) + lpx_delete_prob(lp), lp = NULL; + return lp; +} + +int lpx_write_mps(LPX *lp, const char *fname) +{ /* write problem data in fixed MPS format */ + return glp_write_mps(lp, GLP_MPS_DECK, NULL, fname); +} + +int lpx_read_bas(LPX *lp, const char *fname) +{ /* read LP basis in fixed MPS format */ +#if 0 /* 13/IV-2009 */ + return read_bas(lp, fname); +#else + xassert(lp == lp); + xassert(fname == fname); + xerror("lpx_read_bas: operation not supported\n"); + return 0; +#endif +} + +int lpx_write_bas(LPX *lp, const char *fname) +{ /* write LP basis in fixed MPS format */ +#if 0 /* 13/IV-2009 */ + return write_bas(lp, fname); +#else + xassert(lp == lp); + xassert(fname == fname); + xerror("lpx_write_bas: operation not supported\n"); + return 0; +#endif +} + +LPX *lpx_read_freemps(const char *fname) +{ /* read problem data in free MPS format */ + LPX *lp = lpx_create_prob(); + if (glp_read_mps(lp, GLP_MPS_FILE, NULL, fname)) + lpx_delete_prob(lp), lp = NULL; + return lp; +} + +int lpx_write_freemps(LPX *lp, const char *fname) +{ /* write problem data in free MPS format */ + return glp_write_mps(lp, GLP_MPS_FILE, NULL, fname); +} + +LPX *lpx_read_cpxlp(const char *fname) +{ /* read problem data in CPLEX LP format */ + LPX *lp; + lp = lpx_create_prob(); + if (glp_read_lp(lp, NULL, fname)) + lpx_delete_prob(lp), lp = NULL; + return lp; +} + +int lpx_write_cpxlp(LPX *lp, const char *fname) +{ /* write problem data in CPLEX LP format */ + return glp_write_lp(lp, NULL, fname); +} + +LPX *lpx_read_model(const char *model, const char *data, const char + *output) +{ /* read LP/MIP model written in GNU MathProg language */ + LPX *lp = NULL; + glp_tran *tran; + /* allocate the translator workspace */ + tran = glp_mpl_alloc_wksp(); + /* read model section and optional data section */ + if (glp_mpl_read_model(tran, model, data != NULL)) goto done; + /* read separate data section, if required */ + if (data != NULL) + if (glp_mpl_read_data(tran, data)) goto done; + /* generate the model */ + if (glp_mpl_generate(tran, output)) goto done; + /* build the problem instance from the model */ + lp = glp_create_prob(); + glp_mpl_build_prob(tran, lp); +done: /* free the translator workspace */ + glp_mpl_free_wksp(tran); + /* bring the problem object to the calling program */ + return lp; +} + +int lpx_print_prob(LPX *lp, const char *fname) +{ /* write problem data in plain text format */ + return glp_write_lp(lp, NULL, fname); +} + +int lpx_print_sol(LPX *lp, const char *fname) +{ /* write LP problem solution in printable format */ + return glp_print_sol(lp, fname); +} + +int lpx_print_sens_bnds(LPX *lp, const char *fname) +{ /* write bounds sensitivity information */ + if (glp_get_status(lp) == GLP_OPT && !glp_bf_exists(lp)) + glp_factorize(lp); + return glp_print_ranges(lp, 0, NULL, 0, fname); +} + +int lpx_print_ips(LPX *lp, const char *fname) +{ /* write interior point solution in printable format */ + return glp_print_ipt(lp, fname); +} + +int lpx_print_mip(LPX *lp, const char *fname) +{ /* write MIP problem solution in printable format */ + return glp_print_mip(lp, fname); +} + +int lpx_is_b_avail(glp_prob *lp) +{ /* check if LP basis is available */ + return glp_bf_exists(lp); +} + +int lpx_main(int argc, const char *argv[]) +{ /* stand-alone LP/MIP solver */ + return glp_main(argc, argv); +} + +/* eof */