Initializing help system before first use

XPRSchgqobj

XPRSchgqobj


Purpose
Used to change a single quadratic coefficient in the objective function corresponding to the variable pair (icol,jcol) of the Hessian matrix.
Synopsis
int XPRS_CC XPRSchgqobj(XPRSprob prob, int icol, int jcol, double dval);
Arguments
prob 
The current problem.
icol 
Column index for the first variable in the quadratic term.
jcol 
Column index for the second variable in the quadratic term.
dval 
New value for the coefficient in the quadratic Hessian matrix. If an entry in dval is 0, the corresponding entry will be deleted.
Example
The following code adds the terms [15x12 + 7x1x2]/2 to the objective function:
XPRSchgqobj(prob, 0, 0, 15);
XPRSchgqobj(prob, 0, 1, 3.5);
Further information
1. The columns icol and jcol must already exist in the matrix. If the columns do not exist, they must be added with the routine XPRSaddcols.
2. If icol is not equal to jcol, then both the matrix elements (icol, jcol) and (jcol, icol) are changed to leave the Hessian symmetric.
Related topics

© 2001-2020 Fair Isaac Corporation. All rights reserved. This documentation is the property of Fair Isaac Corporation (“FICO”). Receipt or possession of this documentation does not convey rights to disclose, reproduce, make derivative works, use, or allow others to use it except solely for internal evaluation purposes to determine whether to purchase a license to the software described in this documentation, or as otherwise set forth in a written software license agreement between you and FICO (or a FICO affiliate). Use of this documentation and the software described in it must conform strictly to the foregoing permitted uses, and no other use is permitted.