SLA_RPVGRW
Purpose
SLA_RPVGRW computes the reciprocal pivot growth factor
norm(A)/norm(U). The "max absolute element" norm is used. If this is
much less than 1, the stability of the LU factorization of the
(equilibrated) matrix A could be poor. This also means that the
solution X, estimated condition numbers, and error bounds could be
unreliable.
norm(A)/norm(U). The "max absolute element" norm is used. If this is
much less than 1, the stability of the LU factorization of the
(equilibrated) matrix A could be poor. This also means that the
solution X, estimated condition numbers, and error bounds could be
unreliable.
Arguments
| N |
(input) INTEGER
The number of linear equations, i.e., the order of the
matrix A. N >= 0. |
| NCOLS |
(input) INTEGER
The number of columns of the matrix A. NCOLS >= 0.
|
| A |
(input) REAL array, dimension (LDA,N)
On entry, the N-by-N matrix A.
|
| LDA |
(input) INTEGER
The leading dimension of the array A. LDA >= max(1,N).
|
| AF |
(input) REAL array, dimension (LDAF,N)
The factors L and U from the factorization
|
| A |
= P*L*U as computed by SGETRF.
|
| LDAF |
(input) INTEGER
The leading dimension of the array AF. LDAF >= max(1,N).
|