# dla_gerpvgrw.f man page

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.

**Date:**December 2016

Definition at line 102 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 14 2017 Version 3.8.0 LAPACK