src/glplpx02.c
changeset 1 c445c931472f
     1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/src/glplpx02.c	Mon Dec 06 13:09:21 2010 +0100
     1.3 @@ -0,0 +1,264 @@
     1.4 +/* glplpx02.c */
     1.5 +
     1.6 +/***********************************************************************
     1.7 +*  This code is part of GLPK (GNU Linear Programming Kit).
     1.8 +*
     1.9 +*  Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008,
    1.10 +*  2009, 2010 Andrew Makhorin, Department for Applied Informatics,
    1.11 +*  Moscow Aviation Institute, Moscow, Russia. All rights reserved.
    1.12 +*  E-mail: <mao@gnu.org>.
    1.13 +*
    1.14 +*  GLPK is free software: you can redistribute it and/or modify it
    1.15 +*  under the terms of the GNU General Public License as published by
    1.16 +*  the Free Software Foundation, either version 3 of the License, or
    1.17 +*  (at your option) any later version.
    1.18 +*
    1.19 +*  GLPK is distributed in the hope that it will be useful, but WITHOUT
    1.20 +*  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
    1.21 +*  or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
    1.22 +*  License for more details.
    1.23 +*
    1.24 +*  You should have received a copy of the GNU General Public License
    1.25 +*  along with GLPK. If not, see <http://www.gnu.org/licenses/>.
    1.26 +***********************************************************************/
    1.27 +
    1.28 +#include "glpapi.h"
    1.29 +
    1.30 +/***********************************************************************
    1.31 +*  NAME
    1.32 +*
    1.33 +*  lpx_put_solution - store basic solution components
    1.34 +*
    1.35 +*  SYNOPSIS
    1.36 +*
    1.37 +*  void lpx_put_solution(glp_prob *lp, int inval, const int *p_stat,
    1.38 +*     const int *d_stat, const double *obj_val, const int r_stat[],
    1.39 +*     const double r_prim[], const double r_dual[], const int c_stat[],
    1.40 +*     const double c_prim[], const double c_dual[])
    1.41 +*
    1.42 +*  DESCRIPTION
    1.43 +*
    1.44 +*  The routine lpx_put_solution stores basic solution components to the
    1.45 +*  specified problem object.
    1.46 +*
    1.47 +*  The parameter inval is the basis factorization invalidity flag.
    1.48 +*  If this flag is clear, the current status of the basis factorization
    1.49 +*  remains unchanged. If this flag is set, the routine invalidates the
    1.50 +*  basis factorization.
    1.51 +*
    1.52 +*  The parameter p_stat is a pointer to the status of primal basic
    1.53 +*  solution, which should be specified as follows:
    1.54 +*
    1.55 +*  GLP_UNDEF  - primal solution is undefined;
    1.56 +*  GLP_FEAS   - primal solution is feasible;
    1.57 +*  GLP_INFEAS - primal solution is infeasible;
    1.58 +*  GLP_NOFEAS - no primal feasible solution exists.
    1.59 +*
    1.60 +*  If the parameter p_stat is NULL, the current status of primal basic
    1.61 +*  solution remains unchanged.
    1.62 +*
    1.63 +*  The parameter d_stat is a pointer to the status of dual basic
    1.64 +*  solution, which should be specified as follows:
    1.65 +*
    1.66 +*  GLP_UNDEF  - dual solution is undefined;
    1.67 +*  GLP_FEAS   - dual solution is feasible;
    1.68 +*  GLP_INFEAS - dual solution is infeasible;
    1.69 +*  GLP_NOFEAS - no dual feasible solution exists.
    1.70 +*
    1.71 +*  If the parameter d_stat is NULL, the current status of dual basic
    1.72 +*  solution remains unchanged.
    1.73 +*
    1.74 +*  The parameter obj_val is a pointer to the objective function value.
    1.75 +*  If it is NULL, the current value of the objective function remains
    1.76 +*  unchanged.
    1.77 +*
    1.78 +*  The array element r_stat[i], 1 <= i <= m (where m is the number of
    1.79 +*  rows in the problem object), specifies the status of i-th auxiliary
    1.80 +*  variable, which should be specified as follows:
    1.81 +*
    1.82 +*  GLP_BS - basic variable;
    1.83 +*  GLP_NL - non-basic variable on lower bound;
    1.84 +*  GLP_NU - non-basic variable on upper bound;
    1.85 +*  GLP_NF - non-basic free variable;
    1.86 +*  GLP_NS - non-basic fixed variable.
    1.87 +*
    1.88 +*  If the parameter r_stat is NULL, the current statuses of auxiliary
    1.89 +*  variables remain unchanged.
    1.90 +*
    1.91 +*  The array element r_prim[i], 1 <= i <= m (where m is the number of
    1.92 +*  rows in the problem object), specifies a primal value of i-th
    1.93 +*  auxiliary variable. If the parameter r_prim is NULL, the current
    1.94 +*  primal values of auxiliary variables remain unchanged.
    1.95 +*
    1.96 +*  The array element r_dual[i], 1 <= i <= m (where m is the number of
    1.97 +*  rows in the problem object), specifies a dual value (reduced cost)
    1.98 +*  of i-th auxiliary variable. If the parameter r_dual is NULL, the
    1.99 +*  current dual values of auxiliary variables remain unchanged.
   1.100 +*
   1.101 +*  The array element c_stat[j], 1 <= j <= n (where n is the number of
   1.102 +*  columns in the problem object), specifies the status of j-th
   1.103 +*  structural variable, which should be specified as follows:
   1.104 +*
   1.105 +*  GLP_BS - basic variable;
   1.106 +*  GLP_NL - non-basic variable on lower bound;
   1.107 +*  GLP_NU - non-basic variable on upper bound;
   1.108 +*  GLP_NF - non-basic free variable;
   1.109 +*  GLP_NS - non-basic fixed variable.
   1.110 +*
   1.111 +*  If the parameter c_stat is NULL, the current statuses of structural
   1.112 +*  variables remain unchanged.
   1.113 +*
   1.114 +*  The array element c_prim[j], 1 <= j <= n (where n is the number of
   1.115 +*  columns in the problem object), specifies a primal value of j-th
   1.116 +*  structural variable. If the parameter c_prim is NULL, the current
   1.117 +*  primal values of structural variables remain unchanged.
   1.118 +*
   1.119 +*  The array element c_dual[j], 1 <= j <= n (where n is the number of
   1.120 +*  columns in the problem object), specifies a dual value (reduced cost)
   1.121 +*  of j-th structural variable. If the parameter c_dual is NULL, the
   1.122 +*  current dual values of structural variables remain unchanged. */
   1.123 +
   1.124 +void lpx_put_solution(glp_prob *lp, int inval, const int *p_stat,
   1.125 +      const int *d_stat, const double *obj_val, const int r_stat[],
   1.126 +      const double r_prim[], const double r_dual[], const int c_stat[],
   1.127 +      const double c_prim[], const double c_dual[])
   1.128 +{     GLPROW *row;
   1.129 +      GLPCOL *col;
   1.130 +      int i, j;
   1.131 +      /* invalidate the basis factorization, if required */
   1.132 +      if (inval) lp->valid = 0;
   1.133 +      /* store primal status */
   1.134 +      if (p_stat != NULL)
   1.135 +      {  if (!(*p_stat == GLP_UNDEF  || *p_stat == GLP_FEAS ||
   1.136 +               *p_stat == GLP_INFEAS || *p_stat == GLP_NOFEAS))
   1.137 +            xerror("lpx_put_solution: p_stat = %d; invalid primal statu"
   1.138 +               "s\n", *p_stat);
   1.139 +         lp->pbs_stat = *p_stat;
   1.140 +      }
   1.141 +      /* store dual status */
   1.142 +      if (d_stat != NULL)
   1.143 +      {  if (!(*d_stat == GLP_UNDEF  || *d_stat == GLP_FEAS ||
   1.144 +               *d_stat == GLP_INFEAS || *d_stat == GLP_NOFEAS))
   1.145 +            xerror("lpx_put_solution: d_stat = %d; invalid dual status "
   1.146 +               "\n", *d_stat);
   1.147 +         lp->dbs_stat = *d_stat;
   1.148 +      }
   1.149 +      /* store objective function value */
   1.150 +      if (obj_val != NULL) lp->obj_val = *obj_val;
   1.151 +      /* store row solution components */
   1.152 +      for (i = 1; i <= lp->m; i++)
   1.153 +      {  row = lp->row[i];
   1.154 +         if (r_stat != NULL)
   1.155 +         {  if (!(r_stat[i] == GLP_BS ||
   1.156 +                  row->type == GLP_FR && r_stat[i] == GLP_NF ||
   1.157 +                  row->type == GLP_LO && r_stat[i] == GLP_NL ||
   1.158 +                  row->type == GLP_UP && r_stat[i] == GLP_NU ||
   1.159 +                  row->type == GLP_DB && r_stat[i] == GLP_NL ||
   1.160 +                  row->type == GLP_DB && r_stat[i] == GLP_NU ||
   1.161 +                  row->type == GLP_FX && r_stat[i] == GLP_NS))
   1.162 +               xerror("lpx_put_solution: r_stat[%d] = %d; invalid row s"
   1.163 +                  "tatus\n", i, r_stat[i]);
   1.164 +            row->stat = r_stat[i];
   1.165 +         }
   1.166 +         if (r_prim != NULL) row->prim = r_prim[i];
   1.167 +         if (r_dual != NULL) row->dual = r_dual[i];
   1.168 +      }
   1.169 +      /* store column solution components */
   1.170 +      for (j = 1; j <= lp->n; j++)
   1.171 +      {  col = lp->col[j];
   1.172 +         if (c_stat != NULL)
   1.173 +         {  if (!(c_stat[j] == GLP_BS ||
   1.174 +                  col->type == GLP_FR && c_stat[j] == GLP_NF ||
   1.175 +                  col->type == GLP_LO && c_stat[j] == GLP_NL ||
   1.176 +                  col->type == GLP_UP && c_stat[j] == GLP_NU ||
   1.177 +                  col->type == GLP_DB && c_stat[j] == GLP_NL ||
   1.178 +                  col->type == GLP_DB && c_stat[j] == GLP_NU ||
   1.179 +                  col->type == GLP_FX && c_stat[j] == GLP_NS))
   1.180 +               xerror("lpx_put_solution: c_stat[%d] = %d; invalid colum"
   1.181 +                  "n status\n", j, c_stat[j]);
   1.182 +            col->stat = c_stat[j];
   1.183 +         }
   1.184 +         if (c_prim != NULL) col->prim = c_prim[j];
   1.185 +         if (c_dual != NULL) col->dual = c_dual[j];
   1.186 +      }
   1.187 +      return;
   1.188 +}
   1.189 +
   1.190 +/*----------------------------------------------------------------------
   1.191 +-- lpx_put_mip_soln - store mixed integer solution components.
   1.192 +--
   1.193 +-- *Synopsis*
   1.194 +--
   1.195 +-- #include "glplpx.h"
   1.196 +-- void lpx_put_mip_soln(glp_prob *lp, int i_stat, double row_mipx[],
   1.197 +--    double col_mipx[]);
   1.198 +--
   1.199 +-- *Description*
   1.200 +--
   1.201 +-- The routine lpx_put_mip_soln stores solution components obtained by
   1.202 +-- branch-and-bound solver into the specified problem object.
   1.203 +--
   1.204 +-- NOTE: This routine is intended for internal use only. */
   1.205 +
   1.206 +void lpx_put_mip_soln(glp_prob *lp, int i_stat, double row_mipx[],
   1.207 +      double col_mipx[])
   1.208 +{     GLPROW *row;
   1.209 +      GLPCOL *col;
   1.210 +      int i, j;
   1.211 +      double sum;
   1.212 +      /* store mixed integer status */
   1.213 +#if 0
   1.214 +      if (!(i_stat == LPX_I_UNDEF || i_stat == LPX_I_OPT ||
   1.215 +            i_stat == LPX_I_FEAS  || i_stat == LPX_I_NOFEAS))
   1.216 +         fault("lpx_put_mip_soln: i_stat = %d; invalid mixed integer st"
   1.217 +            "atus", i_stat);
   1.218 +      lp->i_stat = i_stat;
   1.219 +#else
   1.220 +      switch (i_stat)
   1.221 +      {  case LPX_I_UNDEF:
   1.222 +            lp->mip_stat = GLP_UNDEF; break;
   1.223 +         case LPX_I_OPT:
   1.224 +            lp->mip_stat = GLP_OPT;  break;
   1.225 +         case LPX_I_FEAS:
   1.226 +            lp->mip_stat = GLP_FEAS; break;
   1.227 +         case LPX_I_NOFEAS:
   1.228 +            lp->mip_stat = GLP_NOFEAS; break;
   1.229 +         default:
   1.230 +            xerror("lpx_put_mip_soln: i_stat = %d; invalid mixed intege"
   1.231 +               "r status\n", i_stat);
   1.232 +      }
   1.233 +#endif
   1.234 +      /* store row solution components */
   1.235 +      if (row_mipx != NULL)
   1.236 +      {  for (i = 1; i <= lp->m; i++)
   1.237 +         {  row = lp->row[i];
   1.238 +            row->mipx = row_mipx[i];
   1.239 +         }
   1.240 +      }
   1.241 +      /* store column solution components */
   1.242 +      if (col_mipx != NULL)
   1.243 +      {  for (j = 1; j <= lp->n; j++)
   1.244 +         {  col = lp->col[j];
   1.245 +            col->mipx = col_mipx[j];
   1.246 +         }
   1.247 +      }
   1.248 +      /* if the solution is claimed to be integer feasible, check it */
   1.249 +      if (lp->mip_stat == GLP_OPT || lp->mip_stat == GLP_FEAS)
   1.250 +      {  for (j = 1; j <= lp->n; j++)
   1.251 +         {  col = lp->col[j];
   1.252 +            if (col->kind == GLP_IV && col->mipx != floor(col->mipx))
   1.253 +               xerror("lpx_put_mip_soln: col_mipx[%d] = %.*g; must be i"
   1.254 +                  "ntegral\n", j, DBL_DIG, col->mipx);
   1.255 +         }
   1.256 +      }
   1.257 +      /* compute the objective function value */
   1.258 +      sum = lp->c0;
   1.259 +      for (j = 1; j <= lp->n; j++)
   1.260 +      {  col = lp->col[j];
   1.261 +         sum += col->coef * col->mipx;
   1.262 +      }
   1.263 +      lp->mip_obj = sum;
   1.264 +      return;
   1.265 +}
   1.266 +
   1.267 +/* eof */