Module: ppl/ppl Branch: ppl-0_11-branch Commit: f1c00c8f1177749c33c7551d73d853ec561d36d0 URL: http://www.cs.unipr.it/git/gitweb.cgi?p=ppl/ppl.git;a=commit;h=f1c00c8f11777...

Author: Enea Zaffanella zaffanella@cs.unipr.it Date: Fri Sep 17 18:45:33 2010 +0200

Corrected efficiency bugs in the C interface and in MIP_Problem.

---

NEWS | 6 ++++++ interfaces/C/ppl_c_implementation_common.cc | 2 +- src/MIP_Problem.cc | 8 ++++---- src/PIP_Tree.cc | 10 +++++----- 4 files changed, 16 insertions(+), 10 deletions(-)

diff --git a/NEWS b/NEWS index 76dce77..8346e7d 100644 --- a/NEWS +++ b/NEWS @@ -10,6 +10,12 @@ NEWS for version 0.11.1 (release date to be decided) Bugfixes ========

+o Corrected an efficiency bug in the C language interface function + int ppl_Linear_Expression_add_to_coefficient() + +o Corrected an efficiency bug in method + MIP_Problem::compute_generator() + o Corrected a bug affecting the input routine of ppl_lpsol, whereby the inhomogeneous term of the objective function was disregarded.

diff --git a/interfaces/C/ppl_c_implementation_common.cc b/interfaces/C/ppl_c_implementation_common.cc index 3380207..b95451a 100644 --- a/interfaces/C/ppl_c_implementation_common.cc +++ b/interfaces/C/ppl_c_implementation_common.cc @@ -536,7 +536,7 @@ ppl_Linear_Expression_add_to_coefficient(ppl_Linear_Expression_t le, ppl_const_Coefficient_t n) try { Linear_Expression& lle = *to_nonconst(le); const Coefficient& nn = *to_const(n); - lle += nn * Variable(var); + add_mul_assign(lle, nn, Variable(var)); return 0; } CATCH_ALL diff --git a/src/MIP_Problem.cc b/src/MIP_Problem.cc index c388715..641d539 100644 --- a/src/MIP_Problem.cc +++ b/src/MIP_Problem.cc @@ -1425,12 +1425,12 @@ PPL::MIP_Problem::compute_generator() const { if (is_in_base(split_var, row)) { const Row& t_row = tableau[row]; if (t_row[split_var] > 0) { - split_num = -t_row[0]; + neg_assign(split_num, t_row[0]); split_den = t_row[split_var]; } else { split_num = t_row[0]; - split_den = -t_row[split_var]; + neg_assign(split_den, t_row[split_var]); } // We compute the lcm to compute subsequently the difference // between the 2 variables. @@ -1463,7 +1463,7 @@ PPL::MIP_Problem::compute_generator() const { // Finally, build the generator. Linear_Expression expr; for (dimension_type i = external_space_dim; i-- > 0; ) - expr += num[i] * Variable(i); + add_mul_assign(expr, num[i], Variable(i));

MIP_Problem& x = const_cast<MIP_Problem&>(*this); x.last_generator = point(expr, lcm); @@ -1502,7 +1502,7 @@ PPL::MIP_Problem::second_phase() { const dimension_type split_var = mapping[i].second; working_cost[original_var] = new_cost[i]; if (mapping[i].second != 0) - working_cost[split_var] = - new_cost[i]; + neg_assign(working_cost[split_var], new_cost[i]); } // Here the first phase problem succeeded with optimum value zero. // Express the old cost function in terms of the computed base. diff --git a/src/PIP_Tree.cc b/src/PIP_Tree.cc index e3f45c1..004ddfc 100644 --- a/src/PIP_Tree.cc +++ b/src/PIP_Tree.cc @@ -2165,7 +2165,7 @@ PIP_Solution_Node::solve(const PIP_Problem& pip, dimension_type j = 1; for (Variables_Set::const_iterator p = all_params.begin(), p_end = all_params.end(); p != p_end; ++p, ++j) - expr += t_test[j] * Variable(*p); + add_mul_assign(expr, t_test[j], Variable(*p)); using namespace IO_Operators; std::cerr << "Found mixed parameter sign row: " << best_i << ".\n" << "Solution depends on sign of parameter " @@ -2549,8 +2549,8 @@ PIP_Solution_Node::generate_cut(const dimension_type index, Linear_Expression expr1(ctx1[0]); Linear_Expression expr2(ctx2[0]); for (dimension_type j = 1; j <= num_params; ++j, ++p) { - expr1 += ctx1[j] * Variable(*p); - expr2 += ctx2[j] * Variable(*p); + add_mul_assign(expr1, ctx1[j], Variable(*p)); + add_mul_assign(expr2, ctx2[j], Variable(*p)); } std::cout << "Inserting into context: " << Constraint(expr1 >= 0) << " ; " @@ -2594,9 +2594,9 @@ PIP_Solution_Node::generate_cut(const dimension_type index, dimension_type si = 0; for (dimension_type j = 0; j < space_dimension; ++j) { if (parameters.count(j) == 1) - expr += cut_t[ti++] * Variable(j); + add_mul_assign(expr, cut_t[ti++], Variable(j)); else - expr += cut_s[si++] * Variable(j); + add_mul_assign(expr, cut_s[si++], Variable(j)); } std::cout << "Adding cut: " << Constraint(expr + cut_t[0] >= 0)