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XPRBgetrcost

Purpose

Get reduced cost value for a variable.

Synopsis

double XPRBgetrcost(XPRBvar var);  

Argument

var	Reference to a variable.

Return value

Reduced cost value for the variable, 0 in case of an error.

Example

XPRBprob expl2;
XPRBvar x1;
double rcval;
   ...
expl2 = XPRBnewprob("example2");
x1 = XPRBnewvar(expl2, XPRB_UI, "abc3", 1, 100);
XPRBsolve(expl2, "l");
rcval = XPRBgetrcost(x1);

This retrieves the reduced cost value for the variable x1 in the solution to the LP problem.

Further information

This function returns the reduced cost value for a variable. The user may wish to test first whether this variable is part of the problem, for instance by checking that the column number is non-negative.
If this function is called after completion of a global search and an integer solution has been found (that is, if function XPRBgetmipstat returns values XPRB_MIP_SOLUTION or XPRB_MIP_OPTIMAL), it returns the value in the best integer solution. If no integer solution is available after a global search this function outputs a warning and returns 0. In all other cases it returns the reduced cost value in the last LP that has been solved. If this function is used during the execution of an optimization process (for instance in Optimizer library callback functions) it needs to be preceded by a call to XPRBsync with the flag XPRB_XPRS_SOL.