# dla_gerpvgrw.f - Man Page

SRC/dla_gerpvgrw.f

## Synopsis

### Functions/Subroutines

double precision function **dla_gerpvgrw** (n, ncols, a, lda, af, ldaf)**DLA_GERPVGRW**

## Function/Subroutine Documentation

### double precision function dla_gerpvgrw (integer n, integer ncols, double precision, dimension( lda, * ) a, integer lda, double precision, dimension( ldaf, * ) af, integer ldaf)

**DLA_GERPVGRW**

**Purpose:**

DLA_GERPVGRW 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.

**Parameters***N*N is INTEGER The number of linear equations, i.e., the order of the matrix A. N >= 0.

*NCOLS*NCOLS is INTEGER The number of columns of the matrix A. NCOLS >= 0.

*A*A is DOUBLE PRECISION array, dimension (LDA,N) On entry, the N-by-N matrix A.

*LDA*LDA is INTEGER The leading dimension of the array A. LDA >= max(1,N).

*AF*AF is DOUBLE PRECISION array, dimension (LDAF,N) The factors L and U from the factorization A = P*L*U as computed by DGETRF.

*LDAF*LDAF is INTEGER The leading dimension of the array AF. LDAF >= max(1,N).

**Author**Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Definition at line **98** of file **dla_gerpvgrw.f**.

## Author

Generated automatically by Doxygen for LAPACK from the source code.

## Referenced By

The man page dla_gerpvgrw(3) is an alias of dla_gerpvgrw.f(3).

Tue Nov 28 2023 12:08:42 Version 3.12.0 LAPACK