Changeset 1110:ba28dfbea5f2 in lemon-0.x for src/work/marci/lp/max_flow_expression.cc

Timestamp:

01/31/05 18:00:12 (19 years ago)

Author:

marci

Branch:

default

Phase:

public

Convert:

svn:c9d7d8f5-90d6-0310-b91f-818b3a526b0e/lemon/trunk@1509

Message:

new functions for changing lower and upper bounds of variables

File:

• src/work/marci/lp/max_flow_expression.cc (modified) (3 diffs)

src/work/marci/lp/max_flow_expression.cc

@@ -50 +50 @@
   typedef Graph::EdgeMap<ColIt> EdgeIndexMap;
   EdgeIndexMap edge_index_map(g);
-  PrimalMap<Edge, EdgeIndexMap> lp_flow(lp, edge_index_map);
+  PrimalMap<Edge, EdgeIndexMap> flow(lp, edge_index_map);
 
   // capacity function
@@ -56 +56 @@
     ColIt col_it=lp.addCol();
     edge_index_map.set(e, col_it);
-    if (cap[e]==0)
-      lp.setColBounds(col_it, LPSolver::FIXED, 0, cap[e]);
-    else 
-      lp.setColBounds(col_it, LPSolver::DOUBLE, 0, cap[e]);
+    // interesting property in GLPK:
+    // if you change the order of the following two lines, the 
+    // two runs of GLPK are extremely different
+      lp.setColUpperBound(col_it, cap[e]);
+      lp.setColLowerBound(col_it, 0);
   }
   
@@ -80 +81 @@
   }
   lp.solveSimplex();
-  //std::cout << lp.colNum() << std::endl;
-  //std::cout << lp.rowNum() << std::endl;
-  //std::cout << "flow value: "<< lp.getObjVal() << std::endl;
-  for (Graph::EdgeIt e(g); e!=INVALID; ++e) 
-    flow.set(e, lp_flow[e]);
+  cout << "elapsed time: " << ts << endl;
 }