XPRSchgcoef
XPRSchgcoef |
Purpose
Used to change a single coefficient in the
matrix. If the coefficient does not already exist, a new coefficient will be added to the matrix. If many coefficients are being added to a row of the matrix, it may be more efficient to delete the old row of the matrix and add a new row.
Synopsis
int XPRS_CC XPRSchgcoef(XPRSprob prob, int irow, int icol, double dval);
Arguments
|
prob
|
The current problem.
|
|
irow
|
Row index for the coefficient.
|
|
icol
|
Column index for the coefficient.
|
|
dval
|
New value for the coefficient. If
dval is zero, any existing coefficient will be deleted.
|
Related controls
Double
|
Tolerance on matrix elements.
|
Example
In the following, the element in row
2, column
1 of the matrix is changed to
0.33:
XPRSchgcoef(prob,2,1,0.33);
Further information
XPRSchgmcoef
is more efficient than multiple calls to
XPRSchgcoef and should be used in its place in such circumstances.
Related topics
XPRSaddcols,
XPRSaddrows,
XPRSchgmcoef,
XPRSchgmqobj,
XPRSchgobj,
XPRSchgqobj,
XPRSchgrhs,
XPRSgetcols,
XPRSgetrows.