static PyObject* Params_parameter_get(ParamsObject *self,
struct param_getsets *pgs) {
switch (pgs->type) {
case 0: // Boolean.
return PyBool_FromLong(lpx_get_int_parm(LP, pgs->code));
case 1: // Integer.
return PyInt_FromLong(lpx_get_int_parm(LP, pgs->code));
case 2: // Float.
return PyFloat_FromDouble(lpx_get_real_parm(LP, pgs->code));
default: // Um, apparently I made a mistake in the PGS definition array.
PyErr_Format(PyExc_RuntimeError, "parameter type code %d unrecognized",
pgs->type);
return NULL;
}
}
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;
}
void lpx_scale_prob(LPX *lp)
{ /* scale LP/MIP problem data */
int m = lpx_get_num_rows(lp);
int n = lpx_get_num_cols(lp);
int sc_ord = 0, sc_max = 20;
double sc_eps = 0.01;
int i, j;
double *R, *S;
/* initialize R := I and S := I */
R = xcalloc(1+m, sizeof(double));
S = xcalloc(1+n, sizeof(double));
for (i = 1; i <= m; i++) R[i] = 1.0;
for (j = 1; j <= n; j++) S[j] = 1.0;
/* if the problem has no rows/columns, skip computations */
if (m == 0 || n == 0) goto skip;
/* compute the scaling matrices R and S */
switch (lpx_get_int_parm(lp, LPX_K_SCALE))
{ case 0:
/* no scaling */
break;
case 1:
/* equilibration scaling */
eq_scal(m, n, lp, mat, R, S, sc_ord);
break;
case 2:
/* geometric mean scaling */
gm_scal(m, n, lp, mat, R, S, sc_ord, sc_max, sc_eps);
break;
case 3:
/* geometric mean scaling, then equilibration scaling */
gm_scal(m, n, lp, mat, R, S, sc_ord, sc_max, sc_eps);
eq_scal(m, n, lp, mat, R, S, sc_ord);
break;
default:
xassert(lp != lp);
}
skip: /* enter the scaling matrices R and S into the problem object and
thereby perform implicit scaling */
for (i = 1; i <= m; i++) lpx_set_rii(lp, i, R[i]);
for (j = 1; j <= n; j++) lpx_set_sjj(lp, j, S[j]);
xfree(R);
xfree(S);
return;
}
static void show_status(LPX *prob, int prob_m, int prob_nz)
{ int n, j, count;
double x, tol_int;
/* determine the number of structural variables of integer kind
whose current values are still fractional */
n = lpx_get_num_cols(prob);
tol_int = lpx_get_real_parm(prob, LPX_K_TOLINT);
count = 0;
for (j = 1; j <= n; j++)
{ if (lpx_get_col_kind(prob, j) != LPX_IV) continue;
x = lpx_get_col_prim(prob, j);
if (fabs(x - floor(x + 0.5)) <= tol_int) continue;
count++;
}
print("&%6d: obj = %17.9e frac = %5d cuts = %5d (%d)",
lpx_get_int_parm(prob, LPX_K_ITCNT),
lpx_get_obj_val(prob), count,
lpx_get_num_rows(prob) - prob_m,
lpx_get_num_nz(prob) - prob_nz);
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;
}
int main(int argc, char *argv[])
{ LPX *lp;
MPL *mpl = NULL;
int ret;
double start;
/* parse command line parameters */
parse_cmdline(argc, argv);
/* remove all output files specified in the command line */
if (display != NULL) remove(display);
if (out_sol != NULL) remove(out_sol);
if (out_bnds != NULL) remove(out_bnds);
if (out_mps != NULL) remove(out_mps);
if (out_lpt != NULL) remove(out_lpt);
if (out_txt != NULL) remove(out_txt);
if (out_glp != NULL) remove(out_glp);
/* read problem from the input file */
if (in_file == NULL)
{ print("No input file specified; try %s --help", argv[0]);
exit(EXIT_FAILURE);
}
switch (format)
{ case 0:
lp = lpx_read_mps(in_file);
if (lp == NULL)
{ print("MPS file processing error");
exit(EXIT_FAILURE);
}
break;
case 1:
lp = lpx_read_lpt(in_file);
if (lp == NULL)
{ print("CPLEX LP file processing error");
exit(EXIT_FAILURE);
}
break;
case 2:
#if 0 /* 01/VIII-2004 */
lp = lpx_read_model(in_file, in_data, display);
if (lp == NULL)
{ print("Model processing error");
exit(EXIT_FAILURE);
}
#else
/* initialize the translator database */
mpl = mpl_initialize();
/* read model section and optional data section */
ret = mpl_read_model(mpl, in_file, in_data != NULL);
if (ret == 4)
err: { print("Model processing error");
exit(EXIT_FAILURE);
}
insist(ret == 1 || ret == 2);
/* read data section, if necessary */
if (in_data != NULL)
{ insist(ret == 1);
ret = mpl_read_data(mpl, in_data);
if (ret == 4) goto err;
insist(ret == 2);
}
/* generate model */
ret = mpl_generate(mpl, display);
if (ret == 4) goto err;
/* extract problem instance */
lp = lpx_extract_prob(mpl);
insist(lp != NULL);
#endif
if (lpx_get_num_rows(lp) == 0)
{ print("Problem has no rows");
exit(EXIT_FAILURE);
}
if (lpx_get_num_cols(lp) == 0)
{ print("Problem has no columns");
exit(EXIT_FAILURE);
}
break;
case 3:
lp = lpx_read_prob(in_file);
if (lp == NULL)
{ print("GNU LP file processing error");
exit(EXIT_FAILURE);
}
break;
default:
insist(format != format);
}
/* change problem name (if required) */
if (newname != NULL) lpx_set_prob_name(lp, newname);
/* change optimization direction (if required) */
if (dir != 0) lpx_set_obj_dir(lp, dir);
/* write problem in MPS format (if required) */
if (out_mps != NULL)
{ lpx_set_int_parm(lp, LPX_K_MPSORIG, orig);
ret = lpx_write_mps(lp, out_mps);
if (ret != 0)
{ print("Unable to write problem in MPS format");
exit(EXIT_FAILURE);
}
}
/* write problem in CPLEX LP format (if required) */
if (out_lpt != NULL)
{ lpx_set_int_parm(lp, LPX_K_LPTORIG, orig);
ret = lpx_write_lpt(lp, out_lpt);
if (ret != 0)
{ print("Unable to write problem in CPLEX LP format");
exit(EXIT_FAILURE);
}
}
/* write problem in plain text format (if required) */
if (out_txt != NULL)
{ lpx_set_int_parm(lp, LPX_K_LPTORIG, orig);
ret = lpx_print_prob(lp, out_txt);
if (ret != 0)
{ print("Unable to write problem in plain text format");
exit(EXIT_FAILURE);
}
}
/* write problem in GNU LP format (if required) */
if (out_glp != NULL)
{ ret = lpx_write_prob(lp, out_glp);
if (ret != 0)
{ print("Unable to write problem in GNU LP format");
exit(EXIT_FAILURE);
}
}
/* if only data check is required, skip computations */
if (check) goto skip;
/* scale the problem data (if required) */
if (scale && (!presol || method == 1)) lpx_scale_prob(lp);
/* build advanced initial basis (if required) */
if (method == 0 && basis && !presol) lpx_adv_basis(lp);
/* set some control parameters, which might be changed in the
command line */
lpx_set_int_parm(lp, LPX_K_PRICE, price);
if (!relax) lpx_set_real_parm(lp, LPX_K_RELAX, 0.0);
lpx_set_int_parm(lp, LPX_K_PRESOL, presol);
lpx_set_int_parm(lp, LPX_K_BRANCH, branch);
lpx_set_int_parm(lp, LPX_K_BTRACK, btrack);
lpx_set_real_parm(lp, LPX_K_TMLIM, (double)tmlim);
/* solve the problem */
start = utime();
switch (method)
{ case 0:
if (nomip || lpx_get_class(lp) == LPX_LP)
{ ret = lpx_simplex(lp);
if (presol && ret != LPX_E_OK && out_sol != NULL)
print("If you need actual output for non-optimal solu"
"tion, use --nopresol");
}
else
{ method = 2;
lpx_simplex(lp);
if (!intopt)
lpx_integer(lp);
else
lpx_intopt(lp);
}
break;
case 1:
if (nomip || lpx_get_class(lp) == LPX_LP)
lpx_interior(lp);
else
{ print("Interior point method is not able to solve MIP pr"
"oblem; use --simplex");
exit(EXIT_FAILURE);
}
break;
default:
insist(method != method);
}
/* display statistics */
print("Time used: %.1f secs", utime() - start);
print("Memory used: %.1fM (%d bytes)",
(double)lib_env_ptr()->mem_tpeak / (double)(1024 * 1024),
lib_env_ptr()->mem_tpeak);
#if 1 /* 01/VIII-2004 */
if (mpl != NULL && mpl_has_solve_stmt(mpl))
{ int n, j, round;
/* store the solution to the translator database */
n = lpx_get_num_cols(lp);
round = lpx_get_int_parm(lp, LPX_K_ROUND);
lpx_set_int_parm(lp, LPX_K_ROUND, 1);
switch (method)
{ case 0:
for (j = 1; j <= n; j++)
mpl_put_col_value(mpl, j, lpx_get_col_prim(lp, j));
break;
case 1:
for (j = 1; j <= n; j++)
mpl_put_col_value(mpl, j, lpx_ipt_col_prim(lp, j));
break;
case 2:
for (j = 1; j <= n; j++)
mpl_put_col_value(mpl, j, lpx_mip_col_val(lp, j));
break;
default:
insist(method != method);
}
lpx_set_int_parm(lp, LPX_K_ROUND, round);
/* perform postsolving */
ret = mpl_postsolve(mpl, display);
if (ret == 4)
{ print("Model postsolving error");
exit(EXIT_FAILURE);
}
insist(ret == 3);
}
#endif
/* write problem solution found by the solver (if required) */
if (out_sol != NULL)
{ switch (method)
{ case 0:
ret = lpx_print_sol(lp, out_sol);
break;
case 1:
ret = lpx_print_ips(lp, out_sol);
break;
case 2:
ret = lpx_print_mip(lp, out_sol);
break;
default:
insist(method != method);
}
if (ret != 0)
{ print("Unable to write problem solution");
exit(EXIT_FAILURE);
}
}
/* write sensitivity bounds information (if required) */
if (out_bnds != NULL)
{ if (method != 0)
{ print("Cannot write sensitivity bounds information for inte"
"rior-point or MIP solution");
exit(EXIT_FAILURE);
}
ret = lpx_print_sens_bnds(lp, out_bnds);
if (ret != 0)
{ print("Unable to write sensitivity bounds information");
exit(EXIT_FAILURE);
}
}
skip: /* delete the problem object */
lpx_delete_prob(lp);
#if 1 /* 01/VIII-2004 */
/* if the translator database exists, destroy it */
if (mpl != NULL) mpl_terminate(mpl);
#endif
/* check that no memory blocks are still allocated */
insist(lib_env_ptr()->mem_total == 0);
insist(lib_env_ptr()->mem_count == 0);
/* return to the control program */
return 0;
}
int lpx_print_prob(LPX *lp, const char *fname)
{ XFILE *fp;
int m, n, mip, i, j, len, t, type, *ndx;
double coef, lb, ub, *val;
char *str, name[255+1];
xprintf("lpx_write_prob: writing problem data to `%s'...\n",
fname);
fp = xfopen(fname, "w");
if (fp == NULL)
{ xprintf("lpx_write_prob: unable to create `%s' - %s\n",
fname, strerror(errno));
goto fail;
}
m = lpx_get_num_rows(lp);
n = lpx_get_num_cols(lp);
mip = (lpx_get_class(lp) == LPX_MIP);
str = (void *)lpx_get_prob_name(lp);
xfprintf(fp, "Problem: %s\n", str == NULL ? "(unnamed)" : str);
xfprintf(fp, "Class: %s\n", !mip ? "LP" : "MIP");
xfprintf(fp, "Rows: %d\n", m);
if (!mip)
xfprintf(fp, "Columns: %d\n", n);
else
xfprintf(fp, "Columns: %d (%d integer, %d binary)\n",
n, lpx_get_num_int(lp), lpx_get_num_bin(lp));
xfprintf(fp, "Non-zeros: %d\n", lpx_get_num_nz(lp));
xfprintf(fp, "\n");
xfprintf(fp, "*** OBJECTIVE FUNCTION ***\n");
xfprintf(fp, "\n");
switch (lpx_get_obj_dir(lp))
{ case LPX_MIN:
xfprintf(fp, "Minimize:");
break;
case LPX_MAX:
xfprintf(fp, "Maximize:");
break;
default:
xassert(lp != lp);
}
str = (void *)lpx_get_obj_name(lp);
xfprintf(fp, " %s\n", str == NULL ? "(unnamed)" : str);
coef = lpx_get_obj_coef(lp, 0);
if (coef != 0.0)
xfprintf(fp, "%*.*g %s\n", DBL_DIG+7, DBL_DIG, coef,
"(constant term)");
for (i = 1; i <= m; i++)
#if 0
{ coef = lpx_get_row_coef(lp, i);
#else
{ coef = 0.0;
#endif
if (coef != 0.0)
xfprintf(fp, "%*.*g %s\n", DBL_DIG+7, DBL_DIG, coef,
row_name(lp, i, name));
}
for (j = 1; j <= n; j++)
{ coef = lpx_get_obj_coef(lp, j);
if (coef != 0.0)
xfprintf(fp, "%*.*g %s\n", DBL_DIG+7, DBL_DIG, coef,
col_name(lp, j, name));
}
xfprintf(fp, "\n");
xfprintf(fp, "*** ROWS (CONSTRAINTS) ***\n");
ndx = xcalloc(1+n, sizeof(int));
val = xcalloc(1+n, sizeof(double));
for (i = 1; i <= m; i++)
{ xfprintf(fp, "\n");
xfprintf(fp, "Row %d: %s", i, row_name(lp, i, name));
lpx_get_row_bnds(lp, i, &type, &lb, &ub);
switch (type)
{ case LPX_FR:
xfprintf(fp, " free");
break;
case LPX_LO:
xfprintf(fp, " >= %.*g", DBL_DIG, lb);
break;
case LPX_UP:
xfprintf(fp, " <= %.*g", DBL_DIG, ub);
break;
case LPX_DB:
xfprintf(fp, " >= %.*g <= %.*g", DBL_DIG, lb, DBL_DIG,
ub);
break;
case LPX_FX:
xfprintf(fp, " = %.*g", DBL_DIG, lb);
break;
default:
xassert(type != type);
}
xfprintf(fp, "\n");
#if 0
coef = lpx_get_row_coef(lp, i);
#else
coef = 0.0;
#endif
if (coef != 0.0)
xfprintf(fp, "%*.*g %s\n", DBL_DIG+7, DBL_DIG, coef,
"(objective)");
len = lpx_get_mat_row(lp, i, ndx, val);
for (t = 1; t <= len; t++)
xfprintf(fp, "%*.*g %s\n", DBL_DIG+7, DBL_DIG, val[t],
col_name(lp, ndx[t], name));
}
xfree(ndx);
xfree(val);
xfprintf(fp, "\n");
xfprintf(fp, "*** COLUMNS (VARIABLES) ***\n");
ndx = xcalloc(1+m, sizeof(int));
val = xcalloc(1+m, sizeof(double));
for (j = 1; j <= n; j++)
{ xfprintf(fp, "\n");
xfprintf(fp, "Col %d: %s", j, col_name(lp, j, name));
if (mip)
{ switch (lpx_get_col_kind(lp, j))
{ case LPX_CV:
break;
case LPX_IV:
xfprintf(fp, " integer");
break;
default:
xassert(lp != lp);
}
}
lpx_get_col_bnds(lp, j, &type, &lb, &ub);
switch (type)
{ case LPX_FR:
xfprintf(fp, " free");
break;
case LPX_LO:
xfprintf(fp, " >= %.*g", DBL_DIG, lb);
break;
case LPX_UP:
xfprintf(fp, " <= %.*g", DBL_DIG, ub);
break;
case LPX_DB:
xfprintf(fp, " >= %.*g <= %.*g", DBL_DIG, lb, DBL_DIG,
ub);
break;
case LPX_FX:
xfprintf(fp, " = %.*g", DBL_DIG, lb);
break;
default:
xassert(type != type);
}
xfprintf(fp, "\n");
coef = lpx_get_obj_coef(lp, j);
if (coef != 0.0)
xfprintf(fp, "%*.*g %s\n", DBL_DIG+7, DBL_DIG, coef,
"(objective)");
len = lpx_get_mat_col(lp, j, ndx, val);
for (t = 1; t <= len; t++)
xfprintf(fp, "%*.*g %s\n", DBL_DIG+7, DBL_DIG, val[t],
row_name(lp, ndx[t], name));
}
xfree(ndx);
xfree(val);
xfprintf(fp, "\n");
xfprintf(fp, "End of output\n");
xfflush(fp);
if (xferror(fp))
{ xprintf("lpx_write_prob: write error on `%s' - %s\n", fname,
strerror(errno));
goto fail;
}
xfclose(fp);
return 0;
fail: if (fp != NULL) xfclose(fp);
return 1;
}
#undef row_name
#undef col_name
/*----------------------------------------------------------------------
-- lpx_print_sol - write LP problem solution in printable format.
--
-- *Synopsis*
--
-- #include "glplpx.h"
-- int lpx_print_sol(LPX *lp, char *fname);
--
-- *Description*
--
-- The routine lpx_print_sol writes the current basic solution of an LP
-- problem, which is specified by the pointer lp, to a text file, whose
-- name is the character string fname, in printable format.
--
-- Information reported by the routine lpx_print_sol is intended mainly
-- for visual analysis.
--
-- *Returns*
--
-- If the operation was successful, the routine returns zero. Otherwise
-- the routine prints an error message and returns non-zero. */
int lpx_print_sol(LPX *lp, const char *fname)
{ XFILE *fp;
int what, round;
xprintf(
"lpx_print_sol: writing LP problem solution to `%s'...\n",
fname);
fp = xfopen(fname, "w");
if (fp == NULL)
{ xprintf("lpx_print_sol: can't create `%s' - %s\n", fname,
strerror(errno));
goto fail;
}
/* problem name */
{ const char *name;
name = lpx_get_prob_name(lp);
if (name == NULL) name = "";
xfprintf(fp, "%-12s%s\n", "Problem:", name);
}
/* number of rows (auxiliary variables) */
{ int nr;
nr = lpx_get_num_rows(lp);
xfprintf(fp, "%-12s%d\n", "Rows:", nr);
}
/* number of columns (structural variables) */
{ int nc;
nc = lpx_get_num_cols(lp);
xfprintf(fp, "%-12s%d\n", "Columns:", nc);
}
/* number of non-zeros (constraint coefficients) */
{ int nz;
nz = lpx_get_num_nz(lp);
xfprintf(fp, "%-12s%d\n", "Non-zeros:", nz);
}
/* solution status */
{ int status;
status = lpx_get_status(lp);
xfprintf(fp, "%-12s%s\n", "Status:",
status == LPX_OPT ? "OPTIMAL" :
status == LPX_FEAS ? "FEASIBLE" :
status == LPX_INFEAS ? "INFEASIBLE (INTERMEDIATE)" :
status == LPX_NOFEAS ? "INFEASIBLE (FINAL)" :
status == LPX_UNBND ? "UNBOUNDED" :
status == LPX_UNDEF ? "UNDEFINED" : "???");
}
/* objective function */
{ char *name;
int dir;
double obj;
name = (void *)lpx_get_obj_name(lp);
dir = lpx_get_obj_dir(lp);
obj = lpx_get_obj_val(lp);
xfprintf(fp, "%-12s%s%s%.10g %s\n", "Objective:",
name == NULL ? "" : name,
name == NULL ? "" : " = ", obj,
dir == LPX_MIN ? "(MINimum)" :
dir == LPX_MAX ? "(MAXimum)" : "(" "???" ")");
}
/* main sheet */
for (what = 1; what <= 2; what++)
{ int mn, ij;
xfprintf(fp, "\n");
xfprintf(fp, " No. %-12s St Activity Lower bound Upp"
"er bound Marginal\n",
what == 1 ? " Row name" : "Column name");
xfprintf(fp, "------ ------------ -- ------------- -----------"
"-- ------------- -------------\n");
mn = (what == 1 ? lpx_get_num_rows(lp) : lpx_get_num_cols(lp));
for (ij = 1; ij <= mn; ij++)
{ const char *name;
int typx, tagx;
double lb, ub, vx, dx;
if (what == 1)
{ name = lpx_get_row_name(lp, ij);
if (name == NULL) name = "";
lpx_get_row_bnds(lp, ij, &typx, &lb, &ub);
round = lpx_get_int_parm(lp, LPX_K_ROUND);
lpx_set_int_parm(lp, LPX_K_ROUND, 1);
lpx_get_row_info(lp, ij, &tagx, &vx, &dx);
lpx_set_int_parm(lp, LPX_K_ROUND, round);
}
else
{ name = lpx_get_col_name(lp, ij);
if (name == NULL) name = "";
lpx_get_col_bnds(lp, ij, &typx, &lb, &ub);
round = lpx_get_int_parm(lp, LPX_K_ROUND);
lpx_set_int_parm(lp, LPX_K_ROUND, 1);
lpx_get_col_info(lp, ij, &tagx, &vx, &dx);
lpx_set_int_parm(lp, LPX_K_ROUND, round);
}
/* row/column ordinal number */
xfprintf(fp, "%6d ", ij);
/* row column/name */
if (strlen(name) <= 12)
xfprintf(fp, "%-12s ", name);
else
xfprintf(fp, "%s\n%20s", name, "");
/* row/column status */
xfprintf(fp, "%s ",
tagx == LPX_BS ? "B " :
tagx == LPX_NL ? "NL" :
tagx == LPX_NU ? "NU" :
tagx == LPX_NF ? "NF" :
tagx == LPX_NS ? "NS" : "??");
/* row/column primal activity */
xfprintf(fp, "%13.6g ", vx);
/* row/column lower bound */
if (typx == LPX_LO || typx == LPX_DB || typx == LPX_FX)
xfprintf(fp, "%13.6g ", lb);
else
xfprintf(fp, "%13s ", "");
/* row/column upper bound */
if (typx == LPX_UP || typx == LPX_DB)
xfprintf(fp, "%13.6g ", ub);
else if (typx == LPX_FX)
xfprintf(fp, "%13s ", "=");
else
xfprintf(fp, "%13s ", "");
/* row/column dual activity */
if (tagx != LPX_BS)
{ if (dx == 0.0)
xfprintf(fp, "%13s", "< eps");
else
xfprintf(fp, "%13.6g", dx);
}
/* end of line */
xfprintf(fp, "\n");
}
}
xfprintf(fp, "\n");
#if 1
if (lpx_get_prim_stat(lp) != LPX_P_UNDEF &&
lpx_get_dual_stat(lp) != LPX_D_UNDEF)
{ int m = lpx_get_num_rows(lp);
LPXKKT kkt;
xfprintf(fp, "Karush-Kuhn-Tucker optimality conditions:\n\n");
lpx_check_kkt(lp, 1, &kkt);
xfprintf(fp, "KKT.PE: max.abs.err. = %.2e on row %d\n",
kkt.pe_ae_max, kkt.pe_ae_row);
xfprintf(fp, " max.rel.err. = %.2e on row %d\n",
kkt.pe_re_max, kkt.pe_re_row);
switch (kkt.pe_quality)
{ case 'H':
xfprintf(fp, " High quality\n");
break;
case 'M':
xfprintf(fp, " Medium quality\n");
break;
case 'L':
xfprintf(fp, " Low quality\n");
break;
default:
xfprintf(fp, " PRIMAL SOLUTION IS WRONG\n");
break;
}
xfprintf(fp, "\n");
xfprintf(fp, "KKT.PB: max.abs.err. = %.2e on %s %d\n",
kkt.pb_ae_max, kkt.pb_ae_ind <= m ? "row" : "column",
kkt.pb_ae_ind <= m ? kkt.pb_ae_ind : kkt.pb_ae_ind - m);
xfprintf(fp, " max.rel.err. = %.2e on %s %d\n",
kkt.pb_re_max, kkt.pb_re_ind <= m ? "row" : "column",
kkt.pb_re_ind <= m ? kkt.pb_re_ind : kkt.pb_re_ind - m);
switch (kkt.pb_quality)
{ case 'H':
xfprintf(fp, " High quality\n");
break;
case 'M':
xfprintf(fp, " Medium quality\n");
break;
case 'L':
xfprintf(fp, " Low quality\n");
break;
default:
xfprintf(fp, " PRIMAL SOLUTION IS INFEASIBLE\n");
break;
}
xfprintf(fp, "\n");
xfprintf(fp, "KKT.DE: max.abs.err. = %.2e on column %d\n",
kkt.de_ae_max, kkt.de_ae_col);
xfprintf(fp, " max.rel.err. = %.2e on column %d\n",
kkt.de_re_max, kkt.de_re_col);
switch (kkt.de_quality)
{ case 'H':
xfprintf(fp, " High quality\n");
break;
case 'M':
xfprintf(fp, " Medium quality\n");
break;
case 'L':
xfprintf(fp, " Low quality\n");
break;
default:
xfprintf(fp, " DUAL SOLUTION IS WRONG\n");
break;
}
xfprintf(fp, "\n");
xfprintf(fp, "KKT.DB: max.abs.err. = %.2e on %s %d\n",
kkt.db_ae_max, kkt.db_ae_ind <= m ? "row" : "column",
kkt.db_ae_ind <= m ? kkt.db_ae_ind : kkt.db_ae_ind - m);
xfprintf(fp, " max.rel.err. = %.2e on %s %d\n",
kkt.db_re_max, kkt.db_re_ind <= m ? "row" : "column",
kkt.db_re_ind <= m ? kkt.db_re_ind : kkt.db_re_ind - m);
switch (kkt.db_quality)
{ case 'H':
xfprintf(fp, " High quality\n");
break;
case 'M':
xfprintf(fp, " Medium quality\n");
break;
case 'L':
xfprintf(fp, " Low quality\n");
break;
default:
xfprintf(fp, " DUAL SOLUTION IS INFEASIBLE\n");
break;
}
xfprintf(fp, "\n");
}
#endif
#if 1
if (lpx_get_status(lp) == LPX_UNBND)
{ int m = lpx_get_num_rows(lp);
int k = lpx_get_ray_info(lp);
xfprintf(fp, "Unbounded ray: %s %d\n",
k <= m ? "row" : "column", k <= m ? k : k - m);
xfprintf(fp, "\n");
}
#endif
xfprintf(fp, "End of output\n");
xfflush(fp);
if (xferror(fp))
{ xprintf("lpx_print_sol: can't write to `%s' - %s\n", fname,
strerror(errno));
goto fail;
}
xfclose(fp);
return 0;
fail: if (fp != NULL) xfclose(fp);
return 1;
}
int lpx_print_mip(LPX *lp, const char *fname)
{ XFILE *fp;
int what, round;
#if 0
if (lpx_get_class(lp) != LPX_MIP)
fault("lpx_print_mip: error -- not a MIP problem");
#endif
xprintf(
"lpx_print_mip: writing MIP problem solution to `%s'...\n",
fname);
fp = xfopen(fname, "w");
if (fp == NULL)
{ xprintf("lpx_print_mip: can't create `%s' - %s\n", fname,
strerror(errno));
goto fail;
}
/* problem name */
{ const char *name;
name = lpx_get_prob_name(lp);
if (name == NULL) name = "";
xfprintf(fp, "%-12s%s\n", "Problem:", name);
}
/* number of rows (auxiliary variables) */
{ int nr;
nr = lpx_get_num_rows(lp);
xfprintf(fp, "%-12s%d\n", "Rows:", nr);
}
/* number of columns (structural variables) */
{ int nc, nc_int, nc_bin;
nc = lpx_get_num_cols(lp);
nc_int = lpx_get_num_int(lp);
nc_bin = lpx_get_num_bin(lp);
xfprintf(fp, "%-12s%d (%d integer, %d binary)\n", "Columns:",
nc, nc_int, nc_bin);
}
/* number of non-zeros (constraint coefficients) */
{ int nz;
nz = lpx_get_num_nz(lp);
xfprintf(fp, "%-12s%d\n", "Non-zeros:", nz);
}
/* solution status */
{ int status;
status = lpx_mip_status(lp);
xfprintf(fp, "%-12s%s\n", "Status:",
status == LPX_I_UNDEF ? "INTEGER UNDEFINED" :
status == LPX_I_OPT ? "INTEGER OPTIMAL" :
status == LPX_I_FEAS ? "INTEGER NON-OPTIMAL" :
status == LPX_I_NOFEAS ? "INTEGER EMPTY" : "???");
}
/* objective function */
{ char *name;
int dir;
double mip_obj;
name = (void *)lpx_get_obj_name(lp);
dir = lpx_get_obj_dir(lp);
mip_obj = lpx_mip_obj_val(lp);
xfprintf(fp, "%-12s%s%s%.10g %s\n", "Objective:",
name == NULL ? "" : name,
name == NULL ? "" : " = ", mip_obj,
dir == LPX_MIN ? "(MINimum)" :
dir == LPX_MAX ? "(MAXimum)" : "(" "???" ")");
}
/* main sheet */
for (what = 1; what <= 2; what++)
{ int mn, ij;
xfprintf(fp, "\n");
xfprintf(fp, " No. %-12s Activity Lower bound Upp"
"er bound\n",
what == 1 ? " Row name" : "Column name");
xfprintf(fp, "------ ------------ ------------- -----------"
"-- -------------\n");
mn = (what == 1 ? lpx_get_num_rows(lp) : lpx_get_num_cols(lp));
for (ij = 1; ij <= mn; ij++)
{ const char *name;
int kind, typx;
double lb, ub, vx;
if (what == 1)
{ name = lpx_get_row_name(lp, ij);
if (name == NULL) name = "";
kind = LPX_CV;
lpx_get_row_bnds(lp, ij, &typx, &lb, &ub);
round = lpx_get_int_parm(lp, LPX_K_ROUND);
lpx_set_int_parm(lp, LPX_K_ROUND, 1);
vx = lpx_mip_row_val(lp, ij);
lpx_set_int_parm(lp, LPX_K_ROUND, round);
}
else
{ name = lpx_get_col_name(lp, ij);
if (name == NULL) name = "";
kind = lpx_get_col_kind(lp, ij);
lpx_get_col_bnds(lp, ij, &typx, &lb, &ub);
round = lpx_get_int_parm(lp, LPX_K_ROUND);
lpx_set_int_parm(lp, LPX_K_ROUND, 1);
vx = lpx_mip_col_val(lp, ij);
lpx_set_int_parm(lp, LPX_K_ROUND, round);
}
/* row/column ordinal number */
xfprintf(fp, "%6d ", ij);
/* row column/name */
if (strlen(name) <= 12)
xfprintf(fp, "%-12s ", name);
else
xfprintf(fp, "%s\n%20s", name, "");
/* row/column kind */
xfprintf(fp, "%s ",
kind == LPX_CV ? " " : kind == LPX_IV ? "*" : "?");
/* row/column primal activity */
xfprintf(fp, "%13.6g", vx);
/* row/column lower and upper bounds */
switch (typx)
{ case LPX_FR:
break;
case LPX_LO:
xfprintf(fp, " %13.6g", lb);
break;
case LPX_UP:
xfprintf(fp, " %13s %13.6g", "", ub);
break;
case LPX_DB:
xfprintf(fp, " %13.6g %13.6g", lb, ub);
break;
case LPX_FX:
xfprintf(fp, " %13.6g %13s", lb, "=");
break;
default:
xassert(typx != typx);
}
/* end of line */
xfprintf(fp, "\n");
}
}
xfprintf(fp, "\n");
#if 1
if (lpx_mip_status(lp) != LPX_I_UNDEF)
{ int m = lpx_get_num_rows(lp);
LPXKKT kkt;
xfprintf(fp, "Integer feasibility conditions:\n\n");
lpx_check_int(lp, &kkt);
xfprintf(fp, "INT.PE: max.abs.err. = %.2e on row %d\n",
kkt.pe_ae_max, kkt.pe_ae_row);
xfprintf(fp, " max.rel.err. = %.2e on row %d\n",
kkt.pe_re_max, kkt.pe_re_row);
switch (kkt.pe_quality)
{ case 'H':
xfprintf(fp, " High quality\n");
break;
case 'M':
xfprintf(fp, " Medium quality\n");
break;
case 'L':
xfprintf(fp, " Low quality\n");
break;
default:
xfprintf(fp, " SOLUTION IS WRONG\n");
break;
}
xfprintf(fp, "\n");
xfprintf(fp, "INT.PB: max.abs.err. = %.2e on %s %d\n",
kkt.pb_ae_max, kkt.pb_ae_ind <= m ? "row" : "column",
kkt.pb_ae_ind <= m ? kkt.pb_ae_ind : kkt.pb_ae_ind - m);
xfprintf(fp, " max.rel.err. = %.2e on %s %d\n",
kkt.pb_re_max, kkt.pb_re_ind <= m ? "row" : "column",
kkt.pb_re_ind <= m ? kkt.pb_re_ind : kkt.pb_re_ind - m);
switch (kkt.pb_quality)
{ case 'H':
xfprintf(fp, " High quality\n");
break;
case 'M':
xfprintf(fp, " Medium quality\n");
break;
case 'L':
xfprintf(fp, " Low quality\n");
break;
default:
xfprintf(fp, " SOLUTION IS INFEASIBLE\n");
break;
}
xfprintf(fp, "\n");
}
#endif
xfprintf(fp, "End of output\n");
xfflush(fp);
if (xferror(fp))
{ xprintf("lpx_print_mip: can't write to `%s' - %s\n", fname,
strerror(errno));
goto fail;
}
xfclose(fp);
return 0;
fail: if (fp != NULL) xfclose(fp);
return 1;
}
int lpx_print_ips(LPX *lp, const char *fname)
{ XFILE *fp;
int what, round;
xprintf("lpx_print_ips: writing LP problem solution to `%s'...\n",
fname);
fp = xfopen(fname, "w");
if (fp == NULL)
{ xprintf("lpx_print_ips: can't create `%s' - %s\n", fname,
strerror(errno));
goto fail;
}
/* problem name */
{ const char *name;
name = lpx_get_prob_name(lp);
if (name == NULL) name = "";
xfprintf(fp, "%-12s%s\n", "Problem:", name);
}
/* number of rows (auxiliary variables) */
{ int nr;
nr = lpx_get_num_rows(lp);
xfprintf(fp, "%-12s%d\n", "Rows:", nr);
}
/* number of columns (structural variables) */
{ int nc;
nc = lpx_get_num_cols(lp);
xfprintf(fp, "%-12s%d\n", "Columns:", nc);
}
/* number of non-zeros (constraint coefficients) */
{ int nz;
nz = lpx_get_num_nz(lp);
xfprintf(fp, "%-12s%d\n", "Non-zeros:", nz);
}
/* solution status */
{ int status;
status = lpx_ipt_status(lp);
xfprintf(fp, "%-12s%s\n", "Status:",
status == LPX_T_UNDEF ? "INTERIOR UNDEFINED" :
status == LPX_T_OPT ? "INTERIOR OPTIMAL" : "???");
}
/* objective function */
{ char *name;
int dir;
double obj;
name = (void *)lpx_get_obj_name(lp);
dir = lpx_get_obj_dir(lp);
obj = lpx_ipt_obj_val(lp);
xfprintf(fp, "%-12s%s%s%.10g %s\n", "Objective:",
name == NULL ? "" : name,
name == NULL ? "" : " = ", obj,
dir == LPX_MIN ? "(MINimum)" :
dir == LPX_MAX ? "(MAXimum)" : "(" "???" ")");
}
/* main sheet */
for (what = 1; what <= 2; what++)
{ int mn, ij;
xfprintf(fp, "\n");
xfprintf(fp, " No. %-12s Activity Lower bound Upp"
"er bound Marginal\n",
what == 1 ? " Row name" : "Column name");
xfprintf(fp, "------ ------------ ------------- -----------"
"-- ------------- -------------\n");
mn = (what == 1 ? lpx_get_num_rows(lp) : lpx_get_num_cols(lp));
for (ij = 1; ij <= mn; ij++)
{ const char *name;
int typx /*, tagx */;
double lb, ub, vx, dx;
if (what == 1)
{ name = lpx_get_row_name(lp, ij);
if (name == NULL) name = "";
lpx_get_row_bnds(lp, ij, &typx, &lb, &ub);
round = lpx_get_int_parm(lp, LPX_K_ROUND);
lpx_set_int_parm(lp, LPX_K_ROUND, 1);
vx = lpx_ipt_row_prim(lp, ij);
dx = lpx_ipt_row_dual(lp, ij);
lpx_set_int_parm(lp, LPX_K_ROUND, round);
}
else
{ name = lpx_get_col_name(lp, ij);
if (name == NULL) name = "";
lpx_get_col_bnds(lp, ij, &typx, &lb, &ub);
round = lpx_get_int_parm(lp, LPX_K_ROUND);
lpx_set_int_parm(lp, LPX_K_ROUND, 1);
vx = lpx_ipt_col_prim(lp, ij);
dx = lpx_ipt_col_dual(lp, ij);
lpx_set_int_parm(lp, LPX_K_ROUND, round);
}
/* row/column ordinal number */
xfprintf(fp, "%6d ", ij);
/* row column/name */
if (strlen(name) <= 12)
xfprintf(fp, "%-12s ", name);
else
xfprintf(fp, "%s\n%20s", name, "");
/* two positions are currently not used */
xfprintf(fp, " ");
/* row/column primal activity */
xfprintf(fp, "%13.6g ", vx);
/* row/column lower bound */
if (typx == LPX_LO || typx == LPX_DB || typx == LPX_FX)
xfprintf(fp, "%13.6g ", lb);
else
xfprintf(fp, "%13s ", "");
/* row/column upper bound */
if (typx == LPX_UP || typx == LPX_DB)
xfprintf(fp, "%13.6g ", ub);
else if (typx == LPX_FX)
xfprintf(fp, "%13s ", "=");
else
xfprintf(fp, "%13s ", "");
/* row/column dual activity */
xfprintf(fp, "%13.6g", dx);
/* end of line */
xfprintf(fp, "\n");
}
}
xfprintf(fp, "\n");
xfprintf(fp, "End of output\n");
xfflush(fp);
if (xferror(fp))
{ xprintf("lpx_print_ips: can't write to `%s' - %s\n", fname,
strerror(errno));
goto fail;
}
xfclose(fp);
return 0;
fail: if (fp != NULL) xfclose(fp);
return 1;
}
int main(int argc, char *argv[])
{ LPX *lp;
MPL *mpl = NULL;
int ret;
ulong_t start;
/* parse command line parameters */
parse_cmdline(argc, argv);
/* set available memory limit */
if (memlim >= 0)
lib_mem_limit(ulmul(ulset(0, 1048576), ulset(0, memlim)));
/* remove all output files specified in the command line */
if (display != NULL) remove(display);
if (out_bas != NULL) remove(out_bas);
if (out_sol != NULL) remove(out_sol);
if (out_bnds != NULL) remove(out_bnds);
if (out_mps != NULL) remove(out_mps);
if (out_freemps != NULL) remove(out_freemps);
if (out_cpxlp != NULL) remove(out_cpxlp);
if (out_txt != NULL) remove(out_txt);
if (out_glp != NULL) remove(out_glp);
if (log_file != NULL) remove(log_file);
/* open hardcopy file, if necessary */
if (log_file != NULL)
{ if (lib_open_log(log_file))
{ print("Unable to create log file");
exit(EXIT_FAILURE);
}
}
/* read problem data from the input file */
if (in_file == NULL)
{ print("No input file specified; try %s --help", argv[0]);
exit(EXIT_FAILURE);
}
switch (format)
{ case 0:
lp = lpx_read_mps(in_file);
if (lp == NULL)
{ print("MPS file processing error");
exit(EXIT_FAILURE);
}
orig = 1;
break;
case 1:
lp = lpx_read_cpxlp(in_file);
if (lp == NULL)
{ print("CPLEX LP file processing error");
exit(EXIT_FAILURE);
}
break;
case 2:
/* initialize the translator database */
mpl = mpl_initialize();
/* read model section and optional data section */
ret = mpl_read_model(mpl, in_file, in_data != NULL);
if (ret == 4)
err: { print("Model processing error");
exit(EXIT_FAILURE);
}
xassert(ret == 1 || ret == 2);
/* read data section, if necessary */
if (in_data != NULL)
{ xassert(ret == 1);
ret = mpl_read_data(mpl, in_data);
if (ret == 4) goto err;
xassert(ret == 2);
}
/* generate model */
ret = mpl_generate(mpl, display);
if (ret == 4) goto err;
/* extract problem instance */
lp = lpx_extract_prob(mpl);
xassert(lp != NULL);
break;
case 3:
lp = lpx_read_prob(in_file);
if (lp == NULL)
{ print("GNU LP file processing error");
exit(EXIT_FAILURE);
}
break;
case 4:
lp = lpx_read_freemps(in_file);
if (lp == NULL)
{ print("MPS file processing error");
exit(EXIT_FAILURE);
}
break;
default:
xassert(format != format);
}
/* order rows and columns of the constraint matrix */
lpx_order_matrix(lp);
/* change problem name (if required) */
if (newname != NULL) lpx_set_prob_name(lp, newname);
/* change optimization direction (if required) */
if (dir != 0) lpx_set_obj_dir(lp, dir);
/* write problem in fixed MPS format (if required) */
if (out_mps != NULL)
{ lpx_set_int_parm(lp, LPX_K_MPSORIG, orig);
ret = lpx_write_mps(lp, out_mps);
if (ret != 0)
{ print("Unable to write problem in fixed MPS format");
exit(EXIT_FAILURE);
}
}
/* write problem in free MPS format (if required) */
if (out_freemps != NULL)
{ ret = lpx_write_freemps(lp, out_freemps);
if (ret != 0)
{ print("Unable to write problem in free MPS format");
exit(EXIT_FAILURE);
}
}
/* write problem in CPLEX LP format (if required) */
if (out_cpxlp != NULL)
{ ret = lpx_write_cpxlp(lp, out_cpxlp);
if (ret != 0)
{ print("Unable to write problem in CPLEX LP format");
exit(EXIT_FAILURE);
}
}
/* write problem in plain text format (if required) */
if (out_txt != NULL)
{ lpx_set_int_parm(lp, LPX_K_LPTORIG, orig);
ret = lpx_print_prob(lp, out_txt);
if (ret != 0)
{ print("Unable to write problem in plain text format");
exit(EXIT_FAILURE);
}
}
/* write problem in GNU LP format (if required) */
if (out_glp != NULL)
{ ret = lpx_write_prob(lp, out_glp);
if (ret != 0)
{ print("Unable to write problem in GNU LP format");
exit(EXIT_FAILURE);
}
}
/* if only data check is required, skip computations */
if (check) goto skip;
/* scale the problem data (if required) */
if (scale && (!presol || method == 1)) lpx_scale_prob(lp);
/* build initial LP basis */
if (method == 0 && !presol && in_bas == NULL)
{ switch (basis)
{ case 0:
lpx_std_basis(lp);
break;
case 1:
if (lpx_get_num_rows(lp) > 0 && lpx_get_num_cols(lp) > 0)
lpx_adv_basis(lp);
break;
case 2:
if (lpx_get_num_rows(lp) > 0 && lpx_get_num_cols(lp) > 0)
lpx_cpx_basis(lp);
break;
default:
xassert(basis != basis);
}
}
/* or read initial basis from input text file in MPS format */
if (in_bas != NULL)
{ if (method != 0)
{ print("Initial LP basis is useless for interior-point solve"
"r and therefore ignored");
goto nobs;
}
lpx_set_int_parm(lp, LPX_K_MPSORIG, orig);
ret = lpx_read_bas(lp, in_bas);
if (ret != 0)
{ print("Unable to read initial LP basis");
exit(EXIT_FAILURE);
}
if (presol)
{ presol = 0;
print("LP presolver disabled because initial LP basis has b"
"een provided");
}
nobs: ;
}
/* set some control parameters, which might be changed in the
command line */
lpx_set_int_parm(lp, LPX_K_BFTYPE, bf_type);
lpx_set_int_parm(lp, LPX_K_PRICE, price);
if (!relax) lpx_set_real_parm(lp, LPX_K_RELAX, 0.0);
lpx_set_int_parm(lp, LPX_K_PRESOL, presol);
lpx_set_int_parm(lp, LPX_K_BRANCH, branch);
lpx_set_int_parm(lp, LPX_K_BTRACK, btrack);
lpx_set_real_parm(lp, LPX_K_TMLIM, (double)tmlim);
lpx_set_int_parm(lp, LPX_K_BINARIZE, binarize);
lpx_set_int_parm(lp, LPX_K_USECUTS, use_cuts);
/* solve the problem */
start = xtime();
switch (method)
{ case 0:
if (nomip || lpx_get_class(lp) == LPX_LP)
{ ret = (!exact ? lpx_simplex(lp) : lpx_exact(lp));
if (xcheck)
{ if (!presol || ret == LPX_E_OK)
lpx_exact(lp);
else
print("If you need checking final basis for non-op"
"timal solution, use --nopresol");
}
if (presol && ret != LPX_E_OK && (out_bas != NULL ||
out_sol != NULL))
print("If you need actual output for non-optimal solu"
"tion, use --nopresol");
}
else
{ method = 2;
if (!intopt)
{ ret = (!exact ? lpx_simplex(lp) : lpx_exact(lp));
if (xcheck && (!presol || ret == LPX_E_OK))
lpx_exact(lp);
lpx_integer(lp);
}
else
lpx_intopt(lp);
}
break;
case 1:
if (nomip || lpx_get_class(lp) == LPX_LP)
lpx_interior(lp);
else
{ print("Interior-point method is not able to solve MIP pr"
"oblem; use --simplex");
exit(EXIT_FAILURE);
}
break;
default:
xassert(method != method);
}
/* display statistics */
print("Time used: %.1f secs", xdifftime(xtime(), start));
{ ulong_t tpeak;
char buf[50];
lib_mem_usage(NULL, NULL, NULL, &tpeak);
print("Memory used: %.1f Mb (%s bytes)",
(4294967296.0 * tpeak.hi + tpeak.lo) / 1048576.0,
ultoa(tpeak, buf, 10));
}
if (mpl != NULL && mpl_has_solve_stmt(mpl))
{ int n, j, round;
/* store the solution to the translator database */
n = lpx_get_num_cols(lp);
round = lpx_get_int_parm(lp, LPX_K_ROUND);
lpx_set_int_parm(lp, LPX_K_ROUND, 1);
switch (method)
{ case 0:
for (j = 1; j <= n; j++)
mpl_put_col_value(mpl, j, lpx_get_col_prim(lp, j));
break;
case 1:
for (j = 1; j <= n; j++)
mpl_put_col_value(mpl, j, lpx_ipt_col_prim(lp, j));
break;
case 2:
for (j = 1; j <= n; j++)
mpl_put_col_value(mpl, j, lpx_mip_col_val(lp, j));
break;
default:
xassert(method != method);
}
lpx_set_int_parm(lp, LPX_K_ROUND, round);
/* perform postsolving */
ret = mpl_postsolve(mpl);
if (ret == 4)
{ print("Model postsolving error");
exit(EXIT_FAILURE);
}
xassert(ret == 3);
}
/* write final LP basis (if required) */
if (out_bas != NULL)
{ lpx_set_int_parm(lp, LPX_K_MPSORIG, orig);
ret = lpx_write_bas(lp, out_bas);
if (ret != 0)
{ print("Unable to write final LP basis");
exit(EXIT_FAILURE);
}
}
/* write problem solution found by the solver (if required) */
if (out_sol != NULL)
{ switch (method)
{ case 0:
ret = lpx_print_sol(lp, out_sol);
break;
case 1:
ret = lpx_print_ips(lp, out_sol);
break;
case 2:
ret = lpx_print_mip(lp, out_sol);
break;
default:
xassert(method != method);
}
if (ret != 0)
{ print("Unable to write problem solution");
exit(EXIT_FAILURE);
}
}
/* write sensitivity bounds information (if required) */
if (out_bnds != NULL)
{ if (method != 0)
{ print("Cannot write sensitivity bounds information for inte"
"rior-point or MIP solution");
exit(EXIT_FAILURE);
}
ret = lpx_print_sens_bnds(lp, out_bnds);
if (ret != 0)
{ print("Unable to write sensitivity bounds information");
exit(EXIT_FAILURE);
}
}
skip: /* delete the problem object */
lpx_delete_prob(lp);
/* if the translator database exists, destroy it */
if (mpl != NULL) mpl_terminate(mpl);
xassert(gmp_pool_count() == 0);
gmp_free_mem();
/* close the hardcopy file */
if (log_file != NULL) lib_close_log();
/* check that no memory blocks are still allocated */
{ int count;
ulong_t total;
lib_mem_usage(&count, NULL, &total, NULL);
xassert(count == 0);
xassert(total.lo == 0 && total.hi == 0);
}
/* free the library environment */
lib_free_env();
/* return to the control program */
return 0;
}
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;
}
void adv_basis(glp_prob *lp)
{ int m = lpx_get_num_rows(lp);
int n = lpx_get_num_cols(lp);
int i, j, jj, k, size;
int *rn, *cn, *rn_inv, *cn_inv;
int typx, *tagx = xcalloc(1+m+n, sizeof(int));
double lb, ub;
xprintf("Crashing...\n");
if (m == 0)
xerror("glp_adv_basis: problem has no rows\n");
if (n == 0)
xerror("glp_adv_basis: problem has no columns\n");
/* use the routine triang (see above) to find maximal triangular
part of the augmented constraint matrix A~ = (I|-A); in order
to prevent columns of fixed variables to be included in the
triangular part, such columns are implictly removed from the
matrix A~ by the routine adv_mat */
rn = xcalloc(1+m, sizeof(int));
cn = xcalloc(1+m+n, sizeof(int));
size = triang(m, m+n, lp, mat, rn, cn);
if (lpx_get_int_parm(lp, LPX_K_MSGLEV) >= 3)
xprintf("Size of triangular part = %d\n", size);
/* the first size rows and columns of the matrix P*A~*Q (where
P and Q are permutation matrices defined by the arrays rn and
cn) form a lower triangular matrix; build the arrays (rn_inv
and cn_inv), which define the matrices inv(P) and inv(Q) */
rn_inv = xcalloc(1+m, sizeof(int));
cn_inv = xcalloc(1+m+n, sizeof(int));
for (i = 1; i <= m; i++) rn_inv[rn[i]] = i;
for (j = 1; j <= m+n; j++) cn_inv[cn[j]] = j;
/* include the columns of the matrix A~, which correspond to the
first size columns of the matrix P*A~*Q, in the basis */
for (k = 1; k <= m+n; k++) tagx[k] = -1;
for (jj = 1; jj <= size; jj++)
{ j = cn_inv[jj];
/* the j-th column of A~ is the jj-th column of P*A~*Q */
tagx[j] = LPX_BS;
}
/* if size < m, we need to add appropriate columns of auxiliary
variables to the basis */
for (jj = size + 1; jj <= m; jj++)
{ /* the jj-th column of P*A~*Q should be replaced by the column
of the auxiliary variable, for which the only unity element
is placed in the position [jj,jj] */
i = rn_inv[jj];
/* the jj-th row of P*A~*Q is the i-th row of A~, but in the
i-th row of A~ the unity element belongs to the i-th column
of A~; therefore the disired column corresponds to the i-th
auxiliary variable (note that this column doesn't belong to
the triangular part found by the routine triang) */
xassert(1 <= i && i <= m);
xassert(cn[i] > size);
tagx[i] = LPX_BS;
}
/* free working arrays */
xfree(rn);
xfree(cn);
xfree(rn_inv);
xfree(cn_inv);
/* build tags of non-basic variables */
for (k = 1; k <= m+n; k++)
{ if (tagx[k] != LPX_BS)
{ if (k <= m)
lpx_get_row_bnds(lp, k, &typx, &lb, &ub);
else
lpx_get_col_bnds(lp, k-m, &typx, &lb, &ub);
switch (typx)
{ case LPX_FR:
tagx[k] = LPX_NF; break;
case LPX_LO:
tagx[k] = LPX_NL; break;
case LPX_UP:
tagx[k] = LPX_NU; break;
case LPX_DB:
tagx[k] =
(fabs(lb) <= fabs(ub) ? LPX_NL : LPX_NU);
break;
case LPX_FX:
tagx[k] = LPX_NS; break;
default:
xassert(typx != typx);
}
}
}
for (k = 1; k <= m+n; k++)
{ if (k <= m)
lpx_set_row_stat(lp, k, tagx[k]);
else
lpx_set_col_stat(lp, k-m, tagx[k]);
}
xfree(tagx);
return;
}
int lpx_integer(LPX *mip)
{ int m = lpx_get_num_rows(mip);
int n = lpx_get_num_cols(mip);
MIPTREE *tree;
LPX *lp;
int ret, i, j, stat, type, len, *ind;
double lb, ub, coef, *val;
#if 0
/* the problem must be of MIP class */
if (lpx_get_class(mip) != LPX_MIP)
{ print("lpx_integer: problem is not of MIP class");
ret = LPX_E_FAULT;
goto done;
}
#endif
/* an optimal solution of LP relaxation must be known */
if (lpx_get_status(mip) != LPX_OPT)
{ print("lpx_integer: optimal solution of LP relaxation required"
);
ret = LPX_E_FAULT;
goto done;
}
/* bounds of all integer variables must be integral */
for (j = 1; j <= n; j++)
{ if (lpx_get_col_kind(mip, j) != LPX_IV) continue;
type = lpx_get_col_type(mip, j);
if (type == LPX_LO || type == LPX_DB || type == LPX_FX)
{ lb = lpx_get_col_lb(mip, j);
if (lb != floor(lb))
{ print("lpx_integer: integer column %d has non-integer lo"
"wer bound or fixed value %g", j, lb);
ret = LPX_E_FAULT;
goto done;
}
}
if (type == LPX_UP || type == LPX_DB)
{ ub = lpx_get_col_ub(mip, j);
if (ub != floor(ub))
{ print("lpx_integer: integer column %d has non-integer up"
"per bound %g", j, ub);
ret = LPX_E_FAULT;
goto done;
}
}
}
/* it seems all is ok */
if (lpx_get_int_parm(mip, LPX_K_MSGLEV) >= 2)
print("Integer optimization begins...");
/* create the branch-and-bound tree */
tree = mip_create_tree(m, n, lpx_get_obj_dir(mip));
/* set up column kinds */
for (j = 1; j <= n; j++)
tree->int_col[j] = (lpx_get_col_kind(mip, j) == LPX_IV);
/* access the LP relaxation template */
lp = tree->lp;
/* set up the objective function */
tree->int_obj = 1;
for (j = 0; j <= tree->n; j++)
{ coef = lpx_get_obj_coef(mip, j);
lpx_set_obj_coef(lp, j, coef);
if (coef != 0.0 && !(tree->int_col[j] && coef == floor(coef)))
tree->int_obj = 0;
}
if (lpx_get_int_parm(mip, LPX_K_MSGLEV) >= 2 && tree->int_obj)
print("Objective function is integral");
/* set up the constraint matrix */
ind = xcalloc(1+n, sizeof(int));
val = xcalloc(1+n, sizeof(double));
for (i = 1; i <= m; i++)
{ len = lpx_get_mat_row(mip, i, ind, val);
lpx_set_mat_row(lp, i, len, ind, val);
}
xfree(ind);
xfree(val);
/* set up scaling matrices */
for (i = 1; i <= m; i++)
lpx_set_rii(lp, i, lpx_get_rii(mip, i));
for (j = 1; j <= n; j++)
lpx_set_sjj(lp, j, lpx_get_sjj(mip, j));
/* revive the root subproblem */
mip_revive_node(tree, 1);
/* set up row attributes for the root subproblem */
for (i = 1; i <= m; i++)
{ type = lpx_get_row_type(mip, i);
lb = lpx_get_row_lb(mip, i);
ub = lpx_get_row_ub(mip, i);
stat = lpx_get_row_stat(mip, i);
lpx_set_row_bnds(lp, i, type, lb, ub);
lpx_set_row_stat(lp, i, stat);
}
/* set up column attributes for the root subproblem */
for (j = 1; j <= n; j++)
{ type = lpx_get_col_type(mip, j);
lb = lpx_get_col_lb(mip, j);
ub = lpx_get_col_ub(mip, j);
stat = lpx_get_col_stat(mip, j);
lpx_set_col_bnds(lp, j, type, lb, ub);
lpx_set_col_stat(lp, j, stat);
}
/* freeze the root subproblem */
mip_freeze_node(tree);
/* inherit some control parameters and statistics */
tree->msg_lev = lpx_get_int_parm(mip, LPX_K_MSGLEV);
if (tree->msg_lev > 2) tree->msg_lev = 2;
tree->branch = lpx_get_int_parm(mip, LPX_K_BRANCH);
tree->btrack = lpx_get_int_parm(mip, LPX_K_BTRACK);
tree->tol_int = lpx_get_real_parm(mip, LPX_K_TOLINT);
tree->tol_obj = lpx_get_real_parm(mip, LPX_K_TOLOBJ);
tree->tm_lim = lpx_get_real_parm(mip, LPX_K_TMLIM);
lpx_set_int_parm(lp, LPX_K_BFTYPE, lpx_get_int_parm(mip,
LPX_K_BFTYPE));
lpx_set_int_parm(lp, LPX_K_PRICE, lpx_get_int_parm(mip,
LPX_K_PRICE));
lpx_set_real_parm(lp, LPX_K_RELAX, lpx_get_real_parm(mip,
LPX_K_RELAX));
lpx_set_real_parm(lp, LPX_K_TOLBND, lpx_get_real_parm(mip,
LPX_K_TOLBND));
lpx_set_real_parm(lp, LPX_K_TOLDJ, lpx_get_real_parm(mip,
LPX_K_TOLDJ));
lpx_set_real_parm(lp, LPX_K_TOLPIV, lpx_get_real_parm(mip,
LPX_K_TOLPIV));
lpx_set_int_parm(lp, LPX_K_ITLIM, lpx_get_int_parm(mip,
LPX_K_ITLIM));
lpx_set_int_parm(lp, LPX_K_ITCNT, lpx_get_int_parm(mip,
LPX_K_ITCNT));
/* reset the status of MIP solution */
lpx_put_mip_soln(mip, LPX_I_UNDEF, NULL, NULL);
/* try solving the problem */
ret = mip_driver(tree);
/* if an integer feasible solution has been found, copy it to the
MIP problem object */
if (tree->found)
lpx_put_mip_soln(mip, LPX_I_FEAS, &tree->mipx[0],
&tree->mipx[m]);
/* copy back statistics about spent resources */
lpx_set_real_parm(mip, LPX_K_TMLIM, tree->tm_lim);
lpx_set_int_parm(mip, LPX_K_ITLIM, lpx_get_int_parm(lp,
LPX_K_ITLIM));
lpx_set_int_parm(mip, LPX_K_ITCNT, lpx_get_int_parm(lp,
LPX_K_ITCNT));
/* analyze exit code reported by the mip driver */
switch (ret)
{ case MIP_E_OK:
if (tree->found)
{ if (lpx_get_int_parm(mip, LPX_K_MSGLEV) >= 3)
print("INTEGER OPTIMAL SOLUTION FOUND");
lpx_put_mip_soln(mip, LPX_I_OPT, NULL, NULL);
}
else
{ if (lpx_get_int_parm(mip, LPX_K_MSGLEV) >= 3)
print("PROBLEM HAS NO INTEGER FEASIBLE SOLUTION");
lpx_put_mip_soln(mip, LPX_I_NOFEAS, NULL, NULL);
}
ret = LPX_E_OK;
break;
case MIP_E_ITLIM:
if (lpx_get_int_parm(mip, LPX_K_MSGLEV) >= 3)
print("ITERATIONS LIMIT EXCEEDED; SEARCH TERMINATED");
ret = LPX_E_ITLIM;
break;
case MIP_E_TMLIM:
if (lpx_get_int_parm(mip, LPX_K_MSGLEV) >= 3)
print("TIME LIMIT EXCEEDED; SEARCH TERMINATED");
ret = LPX_E_TMLIM;
break;
case MIP_E_ERROR:
if (lpx_get_int_parm(mip, LPX_K_MSGLEV) >= 1)
print("lpx_integer: cannot solve current LP relaxation");
ret = LPX_E_SING;
break;
default:
xassert(ret != ret);
}
/* delete the branch-and-bound tree */
mip_delete_tree(tree);
done: /* return to the application program */
return ret;
}
int lpx_intopt(LPX *_mip)
{ IPP *ipp = NULL;
LPX *orig = _mip, *prob = NULL;
int orig_m, orig_n, i, j, ret, i_stat;
/* the problem must be of MIP class */
if (lpx_get_class(orig) != LPX_MIP)
{ print("lpx_intopt: problem is not of MIP class");
ret = LPX_E_FAULT;
goto done;
}
/* the problem must have at least one row and one column */
orig_m = lpx_get_num_rows(orig);
orig_n = lpx_get_num_cols(orig);
if (!(orig_m > 0 && orig_n > 0))
{ print("lpx_intopt: problem has no rows/columns");
ret = LPX_E_FAULT;
goto done;
}
/* check that each double-bounded row and column has bounds */
for (i = 1; i <= orig_m; i++)
{ if (lpx_get_row_type(orig, i) == LPX_DB)
{ if (lpx_get_row_lb(orig, i) >= lpx_get_row_ub(orig, i))
{ print("lpx_intopt: row %d has incorrect bounds", i);
ret = LPX_E_FAULT;
goto done;
}
}
}
for (j = 1; j <= orig_n; j++)
{ if (lpx_get_col_type(orig, j) == LPX_DB)
{ if (lpx_get_col_lb(orig, j) >= lpx_get_col_ub(orig, j))
{ print("lpx_intopt: column %d has incorrect bounds", j);
ret = LPX_E_FAULT;
goto done;
}
}
}
/* bounds of all integer variables must be integral */
for (j = 1; j <= orig_n; j++)
{ int type;
double lb, ub;
if (lpx_get_col_kind(orig, j) != LPX_IV) continue;
type = lpx_get_col_type(orig, j);
if (type == LPX_LO || type == LPX_DB || type == LPX_FX)
{ lb = lpx_get_col_lb(orig, j);
if (lb != floor(lb))
{ print("lpx_intopt: integer column %d has non-integer low"
"er bound or fixed value %g", j, lb);
ret = LPX_E_FAULT;
goto done;
}
}
if (type == LPX_UP || type == LPX_DB)
{ ub = lpx_get_col_ub(orig, j);
if (ub != floor(ub))
{ print("lpx_intopt: integer column %d has non-integer upp"
"er bound %g", j, ub);
ret = LPX_E_FAULT;
goto done;
}
}
}
/* reset the status of MIP solution */
lpx_put_mip_soln(orig, LPX_I_UNDEF, NULL, NULL);
/* create MIP presolver workspace */
ipp = ipp_create_wksp();
/* load the original problem into the presolver workspace */
ipp_load_orig(ipp, orig);
/* perform basic MIP presolve analysis */
switch (ipp_basic_tech(ipp))
{ case 0:
/* no infeasibility is detected */
break;
case 1:
nopfs: /* primal infeasibility is detected */
print("PROBLEM HAS NO PRIMAL FEASIBLE SOLUTION");
ret = LPX_E_NOPFS;
goto done;
case 2:
/* dual infeasibility is detected */
nodfs: print("LP RELAXATION HAS NO DUAL FEASIBLE SOLUTION");
ret = LPX_E_NODFS;
goto done;
default:
insist(ipp != ipp);
}
/* reduce column bounds */
switch (ipp_reduce_bnds(ipp))
{ case 0: break;
case 1: goto nopfs;
default: insist(ipp != ipp);
}
/* perform basic MIP presolve analysis */
switch (ipp_basic_tech(ipp))
{ case 0: break;
case 1: goto nopfs;
case 2: goto nodfs;
default: insist(ipp != ipp);
}
/* replace general integer variables by sum of binary variables,
if required */
if (lpx_get_int_parm(orig, LPX_K_BINARIZE))
ipp_binarize(ipp);
/* perform coefficient reduction */
ipp_reduction(ipp);
/* if the resultant problem is empty, it has an empty solution,
which is optimal */
if (ipp->row_ptr == NULL || ipp->col_ptr == NULL)
{ insist(ipp->row_ptr == NULL);
insist(ipp->col_ptr == NULL);
print("Objective value = %.10g",
ipp->orig_dir == LPX_MIN ? +ipp->c0 : -ipp->c0);
print("INTEGER OPTIMAL SOLUTION FOUND BY MIP PRESOLVER");
/* allocate recovered solution segment */
ipp->col_stat = ucalloc(1+ipp->ncols, sizeof(int));
ipp->col_mipx = ucalloc(1+ipp->ncols, sizeof(double));
for (j = 1; j <= ipp->ncols; j++) ipp->col_stat[j] = 0;
/* perform MIP postsolve processing */
ipp_postsolve(ipp);
/* unload recovered MIP solution and store it in the original
problem object */
ipp_unload_sol(ipp, orig, LPX_I_OPT);
ret = LPX_E_OK;
goto done;
}
/* build resultant MIP problem object */
prob = ipp_build_prob(ipp);
/* display some statistics */
{ int m = lpx_get_num_rows(prob);
int n = lpx_get_num_cols(prob);
int nnz = lpx_get_num_nz(prob);
int ni = lpx_get_num_int(prob);
int nb = lpx_get_num_bin(prob);
char s[50];
print("lpx_intopt: presolved MIP has %d row%s, %d column%s, %d"
" non-zero%s", m, m == 1 ? "" : "s", n, n == 1 ? "" : "s",
nnz, nnz == 1 ? "" : "s");
if (nb == 0)
strcpy(s, "none of");
else if (ni == 1 && nb == 1)
strcpy(s, "");
else if (nb == 1)
strcpy(s, "one of");
else if (nb == ni)
strcpy(s, "all of");
else
sprintf(s, "%d of", nb);
print("lpx_intopt: %d integer column%s, %s which %s binary",
ni, ni == 1 ? "" : "s", s, nb == 1 ? "is" : "are");
}
/* inherit some control parameters and statistics */
lpx_set_int_parm(prob, LPX_K_PRICE, lpx_get_int_parm(orig,
LPX_K_PRICE));
lpx_set_real_parm(prob, LPX_K_RELAX, lpx_get_real_parm(orig,
LPX_K_RELAX));
lpx_set_real_parm(prob, LPX_K_TOLBND, lpx_get_real_parm(orig,
LPX_K_TOLBND));
lpx_set_real_parm(prob, LPX_K_TOLDJ, lpx_get_real_parm(orig,
LPX_K_TOLDJ));
lpx_set_real_parm(prob, LPX_K_TOLPIV, lpx_get_real_parm(orig,
LPX_K_TOLPIV));
lpx_set_int_parm(prob, LPX_K_ITLIM, lpx_get_int_parm(orig,
LPX_K_ITLIM));
lpx_set_int_parm(prob, LPX_K_ITCNT, lpx_get_int_parm(orig,
LPX_K_ITCNT));
lpx_set_real_parm(prob, LPX_K_TMLIM, lpx_get_real_parm(orig,
LPX_K_TMLIM));
lpx_set_int_parm(prob, LPX_K_BRANCH, lpx_get_int_parm(orig,
LPX_K_BRANCH));
lpx_set_int_parm(prob, LPX_K_BTRACK, lpx_get_int_parm(orig,
LPX_K_BTRACK));
lpx_set_real_parm(prob, LPX_K_TOLINT, lpx_get_real_parm(orig,
LPX_K_TOLINT));
lpx_set_real_parm(prob, LPX_K_TOLOBJ, lpx_get_real_parm(orig,
LPX_K_TOLOBJ));
/* build an advanced initial basis */
lpx_adv_basis(prob);
/* solve LP relaxation */
print("Solving LP relaxation...");
switch (lpx_simplex(prob))
{ case LPX_E_OK:
break;
case LPX_E_ITLIM:
ret = LPX_E_ITLIM;
goto done;
case LPX_E_TMLIM:
ret = LPX_E_TMLIM;
goto done;
default:
print("lpx_intopt: cannot solve LP relaxation");
ret = LPX_E_SING;
goto done;
}
/* analyze status of the basic solution */
switch (lpx_get_status(prob))
{ case LPX_OPT:
break;
case LPX_NOFEAS:
ret = LPX_E_NOPFS;
goto done;
case LPX_UNBND:
ret = LPX_E_NODFS;
goto done;
default:
insist(prob != prob);
}
/* generate cutting planes, if necessary */
if (lpx_get_int_parm(orig, LPX_K_USECUTS))
{ ret = generate_cuts(prob);
if (ret != LPX_E_OK) goto done;
}
/* call the branch-and-bound solver */
ret = lpx_integer(prob);
/* determine status of MIP solution */
i_stat = lpx_mip_status(prob);
if (i_stat == LPX_I_OPT || i_stat == LPX_I_FEAS)
{ /* load MIP solution of the resultant problem into presolver
workspace */
ipp_load_sol(ipp, prob);
/* perform MIP postsolve processing */
ipp_postsolve(ipp);
/* unload recovered MIP solution and store it in the original
problem object */
ipp_unload_sol(ipp, orig, i_stat);
}
else
{ /* just set the status of MIP solution */
lpx_put_mip_soln(orig, i_stat, NULL, NULL);
}
done: /* copy back statistics about spent resources */
if (prob != NULL)
{ lpx_set_int_parm(orig, LPX_K_ITLIM, lpx_get_int_parm(prob,
LPX_K_ITLIM));
lpx_set_int_parm(orig, LPX_K_ITCNT, lpx_get_int_parm(prob,
LPX_K_ITCNT));
lpx_set_real_parm(orig, LPX_K_TMLIM, lpx_get_real_parm(prob,
LPX_K_TMLIM));
}
/* delete the resultant problem object */
if (prob != NULL) lpx_delete_prob(prob);
/* delete MIP presolver workspace */
if (ipp != NULL) ipp_delete_wksp(ipp);
return ret;
}
static int generate_cuts(LPX *prob)
{ int prob_m, prob_n, prob_nz, msg_lev, dual, nrows, it_cnt, ret;
double out_dly, tm_lim, tm_lag = 0.0, tm_beg = utime();
print("Generating cutting planes...");
/* determine the number of rows, columns, and non-zeros on entry
to the routine */
prob_m = lpx_get_num_rows(prob);
prob_n = lpx_get_num_cols(prob);
prob_nz = lpx_get_num_nz(prob);
/* save some control parameters */
msg_lev = lpx_get_int_parm(prob, LPX_K_MSGLEV);
dual = lpx_get_int_parm(prob, LPX_K_DUAL);
out_dly = lpx_get_real_parm(prob, LPX_K_OUTDLY);
tm_lim = lpx_get_real_parm(prob, LPX_K_TMLIM);
/* and set their new values needed for re-optimization */
lpx_set_int_parm(prob, LPX_K_MSGLEV, 1);
lpx_set_int_parm(prob, LPX_K_DUAL, 1);
lpx_set_real_parm(prob, LPX_K_OUTDLY, 10.0);
lpx_set_real_parm(prob, LPX_K_TMLIM, -1.0);
loop: /* main loop starts here */
/* display current status of the problem */
if (utime() - tm_lag >= 5.0 - 0.001)
show_status(prob, prob_m, prob_nz), tm_lag = utime();
/* check if the patience has been exhausted */
if (tm_lim >= 0.0 && tm_lim <= utime() - tm_beg)
{ ret = LPX_E_TMLIM;
goto done;
}
/* not more than 500 cut inequalities are allowed */
if (lpx_get_num_rows(prob) - prob_m >= 500)
{ ret = LPX_E_OK;
goto done;
}
/* not more than 50,000 cut coefficients are allowed */
if (lpx_get_num_nz(prob) - prob_nz >= 50000)
{ ret = LPX_E_OK;
goto done;
}
/* try to generate Gomory's mixed integer cut */
nrows = lpx_get_num_rows(prob);
gen_gomory_cut(prob, prob_n);
if (nrows == lpx_get_num_rows(prob))
{ /* nothing has been generated */
ret = LPX_E_OK;
goto done;
}
/* re-optimize current LP relaxation using dual simplex */
it_cnt = lpx_get_int_parm(prob, LPX_K_ITCNT);
switch (lpx_simplex(prob))
{ case LPX_E_OK:
break;
case LPX_E_ITLIM:
ret = LPX_E_ITLIM;
goto done;
default:
ret = LPX_E_SING;
goto done;
}
if (it_cnt == lpx_get_int_parm(prob, LPX_K_ITCNT))
{ ret = LPX_E_OK;
goto done;
}
/* analyze status of the basic solution */
switch (lpx_get_status(prob))
{ case LPX_OPT:
break;
case LPX_NOFEAS:
ret = LPX_E_NOPFS;
goto done;
default:
insist(prob != prob);
}
/* continue generating cutting planes */
goto loop;
done: /* display final status of the problem */
show_status(prob, prob_m, prob_nz);
switch (ret)
{ case LPX_E_OK:
break;
case LPX_E_NOPFS:
print("PROBLEM HAS NO INTEGER FEASIBLE SOLUTION");
break;
case LPX_E_ITLIM:
print("ITERATIONS LIMIT EXCEEDED; SEARCH TERMINATED");
break;
case LPX_E_TMLIM:
print("TIME LIMIT EXCEEDED; SEARCH TERMINATED");
break;
case LPX_E_SING:
print("lpx_intopt: cannot re-optimize LP relaxation");
break;
default:
insist(ret != ret);
}
/* decrease the time limit by spent amount of the time */
if (tm_lim >= 0.0)
{ tm_lim -= (utime() - tm_beg);
if (tm_lim < 0.0) tm_lim = 0.0;
}
/* restore some control parameters and update statistics */
lpx_set_int_parm(prob, LPX_K_MSGLEV, msg_lev);
lpx_set_int_parm(prob, LPX_K_DUAL, dual);
lpx_set_real_parm(prob, LPX_K_OUTDLY, out_dly);
lpx_set_real_parm(prob, LPX_K_TMLIM, tm_lim);
return ret;
}
int lpx_print_sens_bnds(LPX *lp, char *fname)
{ FILE *fp = NULL;
int what, round;
print("lpx_print_sens_bnds: writing LP problem solution bounds to"
" `%s'...", fname);
#if 1
/* added by mao */
/* this routine needs factorization of the current basis matrix
which, however, does not exist if the basic solution was
obtained by the lp presolver; therefore we should warm up the
basis to be sure that the factorization is valid (note that if
the factorization exists, lpx_warm_up does nothing) */
lpx_warm_up(lp);
#endif
#if 0 /* 21/XII-2003 by mao */
if (lp->b_stat == LPX_B_UNDEF)
#else
if (!lpx_is_b_avail(lp))
#endif
{ print("lpx_print_sens_bnds: basis information not available (m"
"ay be a presolve issue)");
goto fail;
}
fp = ufopen(fname, "w");
if (fp == NULL)
{ print("lpx_print_sens_bnds: can't create `%s' - %s", fname,
strerror(errno));
goto fail;
}
/* problem name */
{ char *name;
name = lpx_get_prob_name(lp);
if (name == NULL) name = "";
fprintf(fp, "%-12s%s\n", "Problem:", name);
}
/* number of rows (auxiliary variables) */
{ int nr;
nr = lpx_get_num_rows(lp);
fprintf(fp, "%-12s%d\n", "Rows:", nr);
}
/* number of columns (structural variables) */
{ int nc;
nc = lpx_get_num_cols(lp);
fprintf(fp, "%-12s%d\n", "Columns:", nc);
}
/* number of non-zeros (constraint coefficients) */
{ int nz;
nz = lpx_get_num_nz(lp);
fprintf(fp, "%-12s%d\n", "Non-zeros:", nz);
}
/* solution status */
{ int status;
status = lpx_get_status(lp);
fprintf(fp, "%-12s%s\n", "Status:",
status == LPX_OPT ? "OPTIMAL" :
status == LPX_FEAS ? "FEASIBLE" :
status == LPX_INFEAS ? "INFEASIBLE (INTERMEDIATE)" :
status == LPX_NOFEAS ? "INFEASIBLE (FINAL)" :
status == LPX_UNBND ? "UNBOUNDED" :
status == LPX_UNDEF ? "UNDEFINED" : "???");
}
/* explanation/warning */
{ fprintf(fp, "\nExplanation: This file presents amounts by whi"
"ch objective coefficients,\n");
fprintf(fp, "constraint bounds, and variable bounds may be cha"
"nged in the original problem\n");
fprintf(fp, "while the optimal basis remains the same. Note t"
"hat the optimal solution\n");
fprintf(fp, "and objective value may change even though the ba"
"sis remains the same.\n");
fprintf(fp, "These bounds assume that all parameters remain fi"
"xed except the one in\n");
fprintf(fp, "question. If more than one parameter is changed,"
" it is possible for the\n");
fprintf(fp, "optimal basis to change even though each paramete"
"r stays within its bounds.\n");
fprintf(fp, "For more details, consult a text on linear progra"
"mming.\n");
}
/* Sensitivity ranges if solution was optimal */
{ int status;
status = lpx_get_status(lp);
if (status == LPX_OPT)
{ int i,j,k,m,n;
int dir;
double max_inc, max_dec;
int *index;
double *val;
fprintf(fp, "\nObjective Coefficient Analysis\n");
fprintf(fp, " No. Column name St Value Max incr"
"ease Max decrease\n");
fprintf(fp, "------ ------------ -- ------------- ---------"
"---- ------------- \n");
n = lpx_get_num_cols(lp);
m = lpx_get_num_rows(lp);
dir = lpx_get_obj_dir(lp);
/* allocate memory for index and val arrays */
index = ucalloc(1+n+m, sizeof(int));
val = ucalloc(1+n+m, sizeof(double));
for (j = 1; j <= n; j++)
{ char *name;
int typx, tagx;
double lb, ub, vx, dx;
name = lpx_get_col_name(lp, j);
if (name == NULL) name = "";
lpx_get_col_bnds(lp, j, &typx, &lb, &ub);
#if 0 /* 21/XII-2003 by mao */
round = lp->round, lp->round = 1;
lpx_get_col_info(lp, j, &tagx, &vx, &dx);
lp->round = round;
#else
round = lpx_get_int_parm(lp, LPX_K_ROUND);
lpx_set_int_parm(lp, LPX_K_ROUND, 1);
lpx_get_col_info(lp, j, &tagx, &vx, &dx);
lpx_set_int_parm(lp, LPX_K_ROUND, round);
#endif
/* row/column ordinal number */
fprintf(fp, "%6d ", j);
/* row column/name */
if (strlen(name) <= 12)
fprintf(fp, "%-12s ", name);
else
fprintf(fp, "%s\n%20s", name, "");
/* row/column status */
fprintf(fp, "%s ",
tagx == LPX_BS ? "B " :
tagx == LPX_NL ? "NL" :
tagx == LPX_NU ? "NU" :
tagx == LPX_NF ? "NF" :
tagx == LPX_NS ? "NS" : "??");
/* objective coefficient */
fprintf(fp, "%13.6g ", lpx_get_obj_coef(lp, j));
if (tagx == LPX_NL)
{ if (dir==LPX_MIN)
{ /* reduced cost must be positive */
max_inc = DBL_MAX; /* really represents infinity */
max_dec = dx;
}
else
{ /* reduced cost must be negative */
max_inc = -dx;
max_dec = DBL_MAX; /* means infinity */
}
}
if (tagx == LPX_NU)
{ if (dir==LPX_MIN)
{ /* reduced cost must be negative */
max_inc = -dx;
max_dec = DBL_MAX;
}
else
{ max_inc = DBL_MAX;
max_dec = dx;
}
}
if (tagx == LPX_NF)
{ /* can't change nonbasic free variables' cost */
max_inc = 0.0;
max_dec = 0.0;
}
if (tagx == LPX_NS)
{ /* doesn't matter what happens to the cost */
max_inc = DBL_MAX;
max_dec = DBL_MAX;
}
if (tagx == LPX_BS)
{ int len;
/* We need to see how this objective coefficient
affects reduced costs of other variables */
len = lpx_eval_tab_row(lp, m+j, index, val);
max_inc = DBL_MAX;
max_dec = DBL_MAX;
for (i = 1; i <= len; i++)
{ /*int stat;*/
int tagx2;
double vx2, dx2;
double delta;
if (index[i]>m)
lpx_get_col_info(lp, index[i]-m, &tagx2, &vx2,
&dx2);
else
lpx_get_row_info(lp, index[i], &tagx2, &vx2,
&dx2);
if (tagx2 == LPX_NL)
{ if (val[i] != 0.0)
{ delta = dx2 / val[i];
if (delta < 0 && -delta < max_inc)
max_inc = -delta;
else if (delta >0 && delta < max_dec)
max_dec = delta;
}
}
if (tagx2 == LPX_NU)
{ if (val[i] != 0.0)
{ delta = dx2 / val[i];
if (delta < 0 && -delta < max_inc)
max_inc = -delta;
else if (delta > 0 && delta < max_dec)
max_dec = delta;
}
}
if (tagx2 == LPX_NF)
{ if (val[i] != 0.0)
{ max_inc = 0.0;
max_dec = 0.0;
}
}
}
}
if (max_inc == -0.0) max_inc = 0.0;
if (max_dec == -0.0) max_dec = 0.0;
if (max_inc == DBL_MAX)
fprintf(fp, "%13s ", "infinity");
else if (max_inc < 1.0e-12 && max_inc > 0)
fprintf(fp, "%13s ", "< eps");
else
fprintf(fp, "%13.6g ", max_inc);
if (max_dec == DBL_MAX)
fprintf(fp, "%13s ", "infinity");
else if (max_dec < 1.0e-12 && max_dec > 0)
fprintf(fp, "%13s ", "< eps");
else
fprintf(fp, "%13.6g ", max_dec);
fprintf(fp, "\n");
}
for (what = 1; what <= 2; what++)
{ int ij, mn;
fprintf(fp, "\n");
fprintf(fp, "%s Analysis\n",
what==1? "Constraint Bounds":"Variable Bounds");
fprintf(fp, " No. %12s St Value Max increase "
" Max decrease\n",
what==1 ? " Row name":"Column name");
fprintf(fp, "------ ------------ -- ------------- ------"
"------- ------------- \n");
mn = what==1 ? m : n;
for (ij = 1; ij <= mn; ij++)
{ char *name;
int typx, tagx;
double lb, ub, vx, dx;
if (what==1)
name = lpx_get_row_name(lp, ij);
else
name = lpx_get_col_name(lp, ij);
if (name == NULL) name = "";
#if 0 /* 21/XII-2003 by mao */
if (what==1)
{ lpx_get_row_bnds(lp, ij, &typx, &lb, &ub);
round = lp->round, lp->round = 1;
lpx_get_row_info(lp, ij, &tagx, &vx, &dx);
lp->round = round;
}
else
{ lpx_get_col_bnds(lp, ij, &typx, &lb, &ub);
round = lp->round, lp->round = 1;
lpx_get_col_info(lp, ij, &tagx, &vx, &dx);
lp->round = round;
}
#else
round = lpx_get_int_parm(lp, LPX_K_ROUND);
lpx_set_int_parm(lp, LPX_K_ROUND, 1);
if (what==1)
{ lpx_get_row_bnds(lp, ij, &typx, &lb, &ub);
lpx_get_row_info(lp, ij, &tagx, &vx, &dx);
}
else
{ lpx_get_col_bnds(lp, ij, &typx, &lb, &ub);
lpx_get_col_info(lp, ij, &tagx, &vx, &dx);
}
lpx_set_int_parm(lp, LPX_K_ROUND, round);
#endif
/* row/column ordinal number */
fprintf(fp, "%6d ", ij);
/* row column/name */
if (strlen(name) <= 12)
fprintf(fp, "%-12s ", name);
else
fprintf(fp, "%s\n%20s", name, "");
/* row/column status */
fprintf(fp, "%s ",
tagx == LPX_BS ? "B " :
tagx == LPX_NL ? "NL" :
tagx == LPX_NU ? "NU" :
tagx == LPX_NF ? "NF" :
tagx == LPX_NS ? "NS" : "??");
fprintf(fp, "\n");
/* first check lower bound */
if (typx == LPX_LO || typx == LPX_DB ||
typx == LPX_FX)
{ int at_lower;
at_lower = 0;
if (tagx == LPX_BS || tagx == LPX_NU)
{ max_inc = vx - lb;
max_dec = DBL_MAX;
}
if (tagx == LPX_NS)
{ max_inc = 0.0;
max_dec = 0.0;
if (dir == LPX_MIN && dx > 0) at_lower = 1;
if (dir == LPX_MAX && dx < 0) at_lower = 1;
}
if (tagx == LPX_NL || at_lower == 1)
{ int len;
/* we have to see how it affects basic
variables */
len = lpx_eval_tab_col(lp, what==1?ij:ij+m,
index, val);
k = lpx_prim_ratio_test(lp, len, index, val, 1,
10e-7);
max_inc = DBL_MAX;
if (k != 0)
{ /*int stat;*/
int tagx2, typx2;
double vx2, dx2, lb2, ub2;
/*double delta;*/
double alpha;
int l;
for (l = 1; l <= len; l++)
if (index[l] == k) alpha = val[l];
if (k>m)
{ lpx_get_col_info(lp, k-m, &tagx2, &vx2,
&dx2);
lpx_get_col_bnds(lp, k-m, &typx2, &lb2,
&ub2);
}
else
{ lpx_get_row_info(lp, k, &tagx2, &vx2,
&dx2);
lpx_get_row_bnds(lp, k, &typx2, &lb2,
&ub2);
}
/* Check which direction;
remember this is upper bound */
if (alpha > 0)
max_inc = (ub2 - vx2)/ alpha;
else
max_inc = (lb2 - vx2)/ alpha;
}
/* now check lower bound */
k = lpx_prim_ratio_test(lp, len, index, val, -1,
10e-7);
max_dec = DBL_MAX;
if (k != 0)
{ /*int stat;*/
int tagx2, typx2;
double vx2, dx2, lb2, ub2;
/*double delta;*/
double alpha;
int l;
for (l = 1; l <= len; l++)
if (index[l] == k) alpha = val[l];
if (k>m)
{ lpx_get_col_info(lp, k-m, &tagx2, &vx2,
&dx2);
lpx_get_col_bnds(lp, k-m, &typx2, &lb2,
&ub2);
}
else
{ lpx_get_row_info(lp, k, &tagx2, &vx2,
&dx2);
lpx_get_row_bnds(lp, k, &typx2, &lb2,
&ub2);
}
/* Check which direction;
remember this is lower bound */
if (alpha > 0)
max_dec = (vx2 - lb2)/ alpha;
else
max_dec = (vx2 - ub2)/ alpha;
}
}
/* bound */
if (typx == LPX_DB || typx == LPX_FX)
{ if (max_inc > ub - lb)
max_inc = ub - lb;
}
fprintf(fp, " LOWER %13.6g ", lb);
if (max_inc == -0.0) max_inc = 0.0;
if (max_dec == -0.0) max_dec = 0.0;
if (max_inc == DBL_MAX)
fprintf(fp, "%13s ", "infinity");
else if (max_inc < 1.0e-12 && max_inc > 0)
fprintf(fp, "%13s ", "< eps");
else
fprintf(fp, "%13.6g ", max_inc);
if (max_dec == DBL_MAX)
fprintf(fp, "%13s ", "infinity");
else if (max_dec < 1.0e-12 && max_dec > 0)
fprintf(fp, "%13s ", "< eps");
else
fprintf(fp, "%13.6g ", max_dec);
fprintf(fp, "\n");
}
/* now check upper bound */
if (typx == LPX_UP || typx == LPX_DB ||
typx == LPX_FX)
{ int at_upper;
at_upper = 0;
if (tagx == LPX_BS || tagx == LPX_NL)
{ max_inc = DBL_MAX;
max_dec = ub - vx;
}
if (tagx == LPX_NS)
{ max_inc = 0.0;
max_dec = 0.0;
if (dir == LPX_MIN && dx < 0) at_upper = 1;
if (dir == LPX_MAX && dx > 0) at_upper = 1;
}
if (tagx == LPX_NU || at_upper == 1)
{ int len;
/* we have to see how it affects basic
variables */
len = lpx_eval_tab_col(lp, what==1?ij:ij+m,
index, val);
k = lpx_prim_ratio_test(lp, len, index, val, 1,
10e-7);
max_inc = DBL_MAX;
if (k != 0)
{ /*int stat;*/
int tagx2, typx2;
double vx2, dx2, lb2, ub2;
/*double delta;*/
double alpha;
int l;
for (l = 1; l <= len; l++)
if (index[l] == k) alpha = val[l];
if (k>m)
{ lpx_get_col_info(lp, k-m, &tagx2, &vx2,
&dx2);
lpx_get_col_bnds(lp, k-m, &typx2, &lb2,
&ub2);
}
else
{ lpx_get_row_info(lp, k, &tagx2, &vx2,
&dx2);
lpx_get_row_bnds(lp, k, &typx2, &lb2,
&ub2);
}
/* Check which direction;
remember this is upper bound */
if (alpha > 0)
max_inc = (ub2 - vx2)/ alpha;
else
max_inc = (lb2 - vx2)/ alpha;
}
/* now check lower bound */
k = lpx_prim_ratio_test(lp, len, index, val, -1,
10e-7);
max_dec = DBL_MAX;
if (k != 0)
{ /*int stat;*/
int tagx2, typx2;
double vx2, dx2, lb2, ub2;
/*double delta;*/
double alpha;
int l;
for (l = 1; l <= len; l++)
if (index[l] == k) alpha = val[l];
if (k>m)
{ lpx_get_col_info(lp, k-m, &tagx2, &vx2,
&dx2);
lpx_get_col_bnds(lp, k-m, &typx2, &lb2,
&ub2);
}
else
{ lpx_get_row_info(lp, k, &tagx2, &vx2,
&dx2);
lpx_get_row_bnds(lp, k, &typx2, &lb2,
&ub2);
}
/* Check which direction;
remember this is lower bound */
if (alpha > 0)
max_dec = (vx2 - lb2)/ alpha;
else
max_dec = (vx2 - ub2)/ alpha;
}
}
if (typx == LPX_DB || typx == LPX_FX)
{ if (max_dec > ub - lb)
max_dec = ub - lb;
}
/* bound */
fprintf(fp, " UPPER %13.6g ", ub);
if (max_inc == -0.0) max_inc = 0.0;
if (max_dec == -0.0) max_dec = 0.0;
if (max_inc == DBL_MAX)
fprintf(fp, "%13s ", "infinity");
else if (max_inc < 1.0e-12 && max_inc > 0)
fprintf(fp, "%13s ", "< eps");
else
fprintf(fp, "%13.6g ", max_inc);
if (max_dec == DBL_MAX)
fprintf(fp, "%13s ", "infinity");
else if (max_dec < 1.0e-12 && max_dec > 0)
fprintf(fp, "%13s ", "< eps");
else
fprintf(fp, "%13.6g ", max_dec);
fprintf(fp, "\n");
}
}
}
/* free the memory we used */
ufree(index);
ufree(val);
}
else fprintf(fp, "No range information since solution is not o"
"ptimal.\n");
}
fprintf(fp, "\n");
fprintf(fp, "End of output\n");
fflush(fp);
if (ferror(fp))
{ print("lpx_print_sens_bnds: can't write to `%s' - %s", fname,
strerror(errno));
goto fail;
}
ufclose(fp);
return 0;
fail: if (fp != NULL) ufclose(fp);
return 1;
}