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Purpose
Check if dual steepest-edge norms are available.
Synopsis
int QStest_row_norms  (QSprob p)
Arguments
p a handle to an initialized problem.
Returns
One if the dual steepest-edge norms exist, and zero otherwise.
Description

This function returns one if dual steepest-edge norms exist, and zero otherwise. If the row norms do not exist (this may happen after some types of problem modifications), then a call to the function QScompute_row_norms or a call to one of the optimization routines will restore them. (Note that row norms will only exist if the LP problem is being solved via the dual steepest-edge simplex algorithm, that is with the dual pricing rule QS_PRICE_DSTEEP.)

Example
/* p is an initialized QSprob, a handle to an existing LP problem.  */
/* Assume we are working with QS_PRICE_DSTEEP pricing rule.         */

int rval, yesno;

yesno = QStest_row_norms (p);
if (yesno == 1) {
    printf ("Row norms exist\n");
} else {
    printf ("Need to compute row norms\n");
    rval = QScompute_row_norms (p);
    if (rval) {
        fprintf (stderr,
                 "Could not compute norms, error code %d\n", rval);
    }
}
 
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Last Updated: November 2003