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XSLPsetcbiterstart

XSLPsetcbiterstart


Purpose
Set a user callback to be called at the start of each SLP iteration
Synopsis
int XPRS_CC XSLPsetcbiterstart(XSLPprob Prob, int (XPRS_CC *UserFunc) (XSLPprob myProb, void *myObject), void *Object);
Arguments
Prob 
The current SLP problem.
UserFunc 
The function to be called at the start of each SLP iteration. UserFunc returns an integer value. If the return value is nonzero, the SLP iterations will stop.
myProb 
The problem passed to the callback function.
myObject 
The user-defined object passed as Object to XSLPsetcbiterstart.
Object 
Address of a user-defined object, which can be used for any purpose by the function. Object is passed to UserFunc as myObject.
Example
The following example sets up a callback to be executed at the start of the optimization to save to save the values of the variables from the previous iteration:
double *cSol;
XSLPsetcbiterstart(Prob, CBIterStart, &cSol);
A suitable callback function might resemble this:
int XPRS_CC CBIterStart(XSLPprob MyProb, void *Obj) {
  XPRSprob xprob;
  double *cSol;
  int nIter;
  cSol = * (double **) Obj;
  XSLPgetintattrib(MyProb, XSLP_ITER, &nIter);
  if (nIter == 0) return 0; /* no previous solution */
  XSLPgetptrattrib(MyProb, XSLP_XPRSPROBLEM, &xprob);
  XPRSgetsol(xprob, cSol, NULL, NULL, NULL);
  return 0;
}
The Object argument is used here to hold the address of the array cSol which we populate with the solution values.
Further information
This callback can be used at the start of each SLP iteration before the optimization begins.
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