[PPL-devel] [GIT] ppl/ppl(master): Avoid unnecessary unbounded precision value in floating point steepest edge .

[Enea Zaffanella]

Module: ppl/ppl
Branch: master
Commit: fbd07c16deb6fa87b4cc8995a548cb53e1a1916b
URL:    http://www.cs.unipr.it/git/gitweb.cgi?p=ppl/ppl.git;a=commit;h=fbd07c16deb6fa87b4cc8995a548cb53e1a1916b

Author: Enea Zaffanella <zaffanella at cs.unipr.it>
Date:   Mon May 11 13:49:40 2009 +0200

Avoid unnecessary unbounded precision value in floating point steepest edge.

---

 src/MIP_Problem.cc |   10 +++++-----
 1 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/src/MIP_Problem.cc b/src/MIP_Problem.cc
index 132912b..e26afe6 100644
--- a/src/MIP_Problem.cc
+++ b/src/MIP_Problem.cc
@@ -857,12 +857,13 @@ PPL::MIP_Problem::process_pending_constraints() {
 
 PPL::dimension_type
 PPL::MIP_Problem::steepest_edge_float_entering_index() const {
-  PPL_DIRTY_TEMP0(mpq_class, real_coeff);
   const dimension_type tableau_num_rows = tableau.num_rows();
   assert(tableau_num_rows == base.size());
   double challenger_num = 0.0;
   double challenger_den = 0.0;
   double current_value = 0.0;
+  double float_tableau_value = 0.0;
+  double float_tableau_denum = 0.0;
   dimension_type entering_index = 0;
   const int cost_sign = sgn(working_cost[working_cost.size() - 1]);
   for (dimension_type j = tableau.num_columns() - 1; j-- > 1; ) {
@@ -880,10 +881,9 @@ PPL::MIP_Problem::steepest_edge_float_entering_index() const {
 	const Coefficient& tableau_ij = tableau_i[j];
 	if (tableau_ij != 0) {
 	  assert(tableau_i[base[i]] != 0);
-	  assign_r(real_coeff.get_num(), tableau_ij, ROUND_NOT_NEEDED);
-	  assign_r(real_coeff.get_den(), tableau_i[base[i]], ROUND_NOT_NEEDED);
-	  real_coeff.canonicalize();
-	  double float_tableau_value = real_coeff.get_d();
+	  assign_r(float_tableau_value, tableau_ij, ROUND_IGNORE);
+	  assign_r(float_tableau_denum, tableau_i[base[i]], ROUND_IGNORE);
+	  float_tableau_value /= float_tableau_denum;
 	  challenger_den += float_tableau_value * float_tableau_value;
 	}
       }