simplex-glpk with modified glpk for fpgaHEADmaster

1 files changed, 1505 insertions, 0 deletions

diff --git a/glpk-5.0/examples/oldapi/lpx.c b/glpk-5.0/examples/oldapi/lpx.c
new file mode 100644
index 0000000..c508306
--- /dev/null
+++ b/glpk-5.0/examples/oldapi/lpx.c
@@ -0,0 +1,1505 @@
+/* lpx.c (old GLPK API) */
+
+/* Written by Andrew Makhorin <mao@gnu.org>, August 2013. */
+
+/* This file contains routines that implement the old GLPK API as it
+*  was defined in GLPK 4.48.
+*
+*  To compile an existing project using these routines you need to add
+*  to the project this file and the header lpx.h.
+*
+*  Please note that you may mix calls to old and new GLPK API routines
+*  (except calls to glp_create_prob and glp_delete_prob). */
+
+#include <float.h>
+#include <limits.h>
+#include "lpx.h"
+
+#define xassert glp_assert
+#define xerror  glp_error
+
+struct CPS
+{     /* control parameters */
+      LPX *lp;
+      /* pointer to corresponding problem object */
+      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 */
+      struct CPS *link;
+      /* pointer to CPS for another problem object */
+};
+
+static struct CPS *cps_ptr = NULL;
+/* initial pointer to CPS linked list */
+
+static struct CPS *find_cps(LPX *lp)
+{     /* find CPS for specified problem object */
+      struct CPS *cps;
+      for (cps = cps_ptr; cps != NULL; cps = cps->link)
+         if (cps->lp == lp) break;
+      /* if cps is NULL (not found), the problem object was created
+         with glp_create_prob rather than with lpx_create_prob */
+      xassert(cps != NULL);
+      return cps;
+}
+
+static void reset_cps(struct CPS *cps)
+{     /* reset control parameters to default values */
+      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;
+      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;
+}
+
+LPX *lpx_create_prob(void)
+{     /* create problem object */
+      LPX *lp;
+      struct CPS *cps;
+      lp = glp_create_prob();
+      cps = glp_alloc(1, sizeof(struct CPS));
+      cps->lp = lp;
+      reset_cps(cps);
+      cps->link = cps_ptr;
+      cps_ptr = cps;
+      return lp;
+}
+
+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 */
+      struct CPS *cps = find_cps(lp);
+      if (cps_ptr == cps)
+         cps_ptr = cps->link;
+      else
+      {  struct CPS *prev;
+         for (prev = cps_ptr; prev != NULL; prev = prev->link)
+            if (prev->link == cps) break;
+         xassert(prev != NULL);
+         prev->link = cps->link;
+      }
+      glp_free(cps);
+      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 m = glp_get_num_rows(lp);
+      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 - m;
+      kkt->de_re_max = re_max;
+      if (re_ind == 0)
+         kkt->de_re_col = 0;
+      else
+         kkt->de_re_col = ae_ind - 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;
+}
+
+void lpx_reset_parms(LPX *lp)
+{     /* reset control parameters to default values */
+      struct CPS *cps = find_cps(lp);
+      reset_cps(cps);
+      return;
+}
+
+void lpx_set_int_parm(LPX *lp, int parm, int val)
+{     /* set (change) integer control parameter */
+      struct CPS *cps = find_cps(lp);
+      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:
+            glp_set_it_cnt(lp, 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:
+            {  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);
+            }
+            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 */
+      struct CPS *cps = find_cps(lp);
+      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 = glp_get_it_cnt(lp); 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:
+            {  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;
+         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 */
+      struct CPS *cps = find_cps(lp);
+      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);
+            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);
+            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 */
+      struct CPS *cps = find_cps(lp);
+      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 */
+      xassert(lp == lp);
+      xassert(fname == fname);
+      xerror("lpx_read_bas: operation not supported\n");
+      return 0;
+}
+
+int lpx_write_bas(LPX *lp, const char *fname)
+{     /* write LP basis in fixed MPS format */
+      xassert(lp == lp);
+      xassert(fname == fname);
+      xerror("lpx_write_bas: operation not supported\n");
+      return 0;
+}
+
+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 = lpx_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 */