On exit:
WORK1 contains the reciprocal pivot growth factor
A/U. The ‘max absolute element’ norm is used. If
WORK1 is much less than
1, then the stability of the
LU factorization of the (equilibrated) matrix
A could be poor. This also means that the solution
X, condition estimate
RCOND, and forward error bound
FERR could be unreliable. If the factorization fails with
INFO>0 and INFO≤N, then
WORK1 contains the reciprocal pivot growth factor for the leading
INFO columns of
A.