# dla_porpvgrw.f(3) [centos man page]

```dla_porpvgrw.f(3)						      LAPACK							 dla_porpvgrw.f(3)

NAME
dla_porpvgrw.f -

SYNOPSIS
Functions/Subroutines
DOUBLE PRECISION function dla_porpvgrw (UPLO, NCOLS, A, LDA, AF, LDAF, WORK)
DLA_PORPVGRW computes the reciprocal pivot growth factor norm(A)/norm(U) for a symmetric or Hermitian positive-definite matrix.

Function/Subroutine Documentation
DOUBLE PRECISION function dla_porpvgrw (character*1UPLO, integerNCOLS, double precision, dimension( lda, * )A, integerLDA, double precision,
dimension( ldaf, * )AF, integerLDAF, double precision, dimension( * )WORK)
DLA_PORPVGRW computes the reciprocal pivot growth factor norm(A)/norm(U) for a symmetric or Hermitian positive-definite matrix.

Purpose:

DLA_PORPVGRW 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:
UPLO

UPLO is CHARACTER*1
= 'U':  Upper triangle of A is stored;
= 'L':  Lower triangle of A is stored.

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 triangular factor U or L from the Cholesky factorization
A = U**T*U or A = L*L**T, as computed by DPOTRF.

LDAF

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

WORK

WORK is DOUBLE PRECISION array, dimension (2*N)

Author:
Univ. of Tennessee

Univ. of California Berkeley

NAG Ltd.

Date:
September 2012

Definition at line 106 of file dla_porpvgrw.f.

Author
Generated automatically by Doxygen for LAPACK from the source code.

Version 3.4.2							  Tue Sep 25 2012						 dla_porpvgrw.f(3)```

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```sla_porpvgrw.f(3)						      LAPACK							 sla_porpvgrw.f(3)

NAME
sla_porpvgrw.f -

SYNOPSIS
Functions/Subroutines
REAL function sla_porpvgrw (UPLO, NCOLS, A, LDA, AF, LDAF, WORK)
SLA_PORPVGRW computes the reciprocal pivot growth factor norm(A)/norm(U) for a symmetric or Hermitian positive-definite matrix.

Function/Subroutine Documentation
REAL function sla_porpvgrw (character*1UPLO, integerNCOLS, real, dimension( lda, * )A, integerLDA, real, dimension( ldaf, * )AF, integerLDAF,
real, dimension( * )WORK)
SLA_PORPVGRW computes the reciprocal pivot growth factor norm(A)/norm(U) for a symmetric or Hermitian positive-definite matrix.

Purpose:

SLA_PORPVGRW 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:
UPLO

UPLO is CHARACTER*1
= 'U':  Upper triangle of A is stored;
= 'L':  Lower triangle of A is stored.

NCOLS

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

A

A is REAL 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 REAL array, dimension (LDAF,N)
The triangular factor U or L from the Cholesky factorization
A = U**T*U or A = L*L**T, as computed by SPOTRF.

LDAF

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

WORK

WORK is REAL array, dimension (2*N)

Author:
Univ. of Tennessee

Univ. of California Berkeley

NAG Ltd.

Date:
September 2012

Definition at line 105 of file sla_porpvgrw.f.

Author
Generated automatically by Doxygen for LAPACK from the source code.

Version 3.4.2							  Tue Sep 25 2012						 sla_porpvgrw.f(3)```
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