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deba@inf.elte.hu
deba@inf.elte.hu
Fixing presolver and basis handling (#255)
0 2 0
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2 files changed with 60 insertions and 6 deletions:
↑ Collapse diff ↑
Ignore white space 6 line context
... ...
@@ -533,11 +533,13 @@
533 533
  GlpkLp::GlpkLp()
534 534
    : LpBase(), LpSolver(), GlpkBase() {
535 535
    messageLevel(MESSAGE_NO_OUTPUT);
536
    presolver(false);
536 537
  }
537 538

	
538 539
  GlpkLp::GlpkLp(const GlpkLp& other)
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    : LpBase(other), LpSolver(other), GlpkBase(other) {
540 541
    messageLevel(MESSAGE_NO_OUTPUT);
542
    presolver(false);
541 543
  }
542 544

	
543 545
  GlpkLp* GlpkLp::newSolver() const { return new GlpkLp; }
... ...
@@ -574,8 +576,24 @@
574 576
      smcp.msg_lev = GLP_MSG_ALL;
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      break;
576 578
    }
579
    smcp.presolve = _presolve;
577 580

	
578
    if (glp_simplex(lp, &smcp) != 0) return UNSOLVED;
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    // If the basis is not valid we get an error return value.
582
    // In this case we can try to create a new basis.
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    switch (glp_simplex(lp, &smcp)) {
584
    case 0:
585
      break;
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    case GLP_EBADB:
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    case GLP_ESING:
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    case GLP_ECOND:
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      lpx_set_int_parm(lp, LPX_K_MSGLEV, smcp.msg_lev);
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      glp_adv_basis(lp, 0);
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      if (glp_simplex(lp, &smcp) != 0) return UNSOLVED;
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      break;
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    default:
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      return UNSOLVED;
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    }
596

	
579 597
    return SOLVED;
580 598
  }
581 599

	
... ...
@@ -600,8 +618,23 @@
600 618
      break;
601 619
    }
602 620
    smcp.meth = GLP_DUAL;
621
    smcp.presolve = _presolve;
603 622

	
604
    if (glp_simplex(lp, &smcp) != 0) return UNSOLVED;
623
    // If the basis is not valid we get an error return value.
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    // In this case we can try to create a new basis.
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    switch (glp_simplex(lp, &smcp)) {
626
    case 0:
627
      break;
628
    case GLP_EBADB:
629
    case GLP_ESING:
630
    case GLP_ECOND:
631
      lpx_set_int_parm(lp, LPX_K_MSGLEV, smcp.msg_lev);
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      glp_adv_basis(lp, 0);
633
      if (glp_simplex(lp, &smcp) != 0) return UNSOLVED;
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      break;
635
    default:
636
      return UNSOLVED;
637
    }
605 638
    return SOLVED;
606 639
  }
607 640

	
... ...
@@ -819,8 +852,8 @@
819 852
    }
820 853
  }
821 854

	
822
  void GlpkLp::presolver(bool b) {
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    lpx_set_int_parm(lp, LPX_K_PRESOL, b ? 1 : 0);
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  void GlpkLp::presolver(bool presolve) {
856
    _presolve = presolve;
824 857
  }
825 858

	
826 859
  void GlpkLp::messageLevel(MessageLevel m) {
... ...
@@ -881,7 +914,22 @@
881 914
    }
882 915
    smcp.meth = GLP_DUAL;
883 916

	
884
    if (glp_simplex(lp, &smcp) != 0) return UNSOLVED;
917
    // If the basis is not valid we get an error return value.
918
    // In this case we can try to create a new basis.
919
    switch (glp_simplex(lp, &smcp)) {
920
    case 0:
921
      break;
922
    case GLP_EBADB:
923
    case GLP_ESING:
924
    case GLP_ECOND:
925
      lpx_set_int_parm(lp, LPX_K_MSGLEV, smcp.msg_lev);
926
      glp_adv_basis(lp, 0);
927
      if (glp_simplex(lp, &smcp) != 0) return UNSOLVED;
928
      break;
929
    default:
930
      return UNSOLVED;
931
    }
932

	
885 933
    if (glp_get_status(lp) != GLP_OPT) return SOLVED;
886 934

	
887 935
    glp_iocp iocp;
Ignore white space 6 line context
... ...
@@ -178,12 +178,18 @@
178 178
    ///Solve with dual simplex
179 179
    SolveExitStatus solveDual();
180 180

	
181
  private:
182

	
183
    bool _presolve;
184

	
185
  public:
186

	
181 187
    ///Turns on or off the presolver
182 188

	
183 189
    ///Turns on (\c b is \c true) or off (\c b is \c false) the presolver
184 190
    ///
185 191
    ///The presolver is off by default.
186
    void presolver(bool b);
192
    void presolver(bool presolve);
187 193

	
188 194
    ///Enum for \c messageLevel() parameter
189 195
    enum MessageLevel {
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