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XPRBaddcuts

Purpose

Add cuts to a problem.

Synopsis

int XPRBaddcuts(XPRBprob prob, XPRBcut *cta, int num);

Arguments

prob	Reference to a problem.
cta	Array of previously defined cuts.
num	Number of cuts in cta.

Return value

0 if function executed successfully, 1 otherwise.

Example

The example shows how to set up the cut manager node callback to add three previously defined cuts ca in node 2 of the MIP search.

XPRBcut ca[3];
XPRBprob expl1;

int XPRS_CC usrcme(XPRSprob oprob, void* vd)
{              
  int num;
  XPRSgetintattrib(oprob, XPRS_NODES, &num);
  if(num == 2) XPRBaddcuts(expl1, ca, 3); 
  return 0;
}

int main(int argc, char **argv)
{
  XPRSprob oprob;
  expl1 = XPRBnewprob("cutexample");
  ...                    /* Define the problem and the cuts 'ca' */
  XPRBsetcutmode(expl1, 1);             /* Enable the cut mode */
  oprob = XPRBgetXPRSprob(expl1);       /* Get Optimizer problem */
  XPRSsetcbcutmgr(oprob, usrcme, NULL); /* Set cut mgr. callback */
  XPRBsolve(expl1, "g");                /* Solve the MIP problem */
}

Further information

This function adds previously defined cuts to the problem in Xpress-Optimizer. It may only be called from within the Xpress-Optimizer cut manager callback functions. BCL does not check for doubles, that is, if the user defines the same cut twice it will be added twice to the matrix. Cuts added at a node during the branch and bound search remain valid for all child nodes but are removed at all other nodes.