dpotrf.f man page

dpotrf.f —

Synopsis

Functions/Subroutines

subroutine dpotrf (UPLO, N, A, LDA, INFO)
DPOTRF

Function/Subroutine Documentation

subroutine dpotrf (characterUPLO, integerN, double precision, dimension( lda, * )A, integerLDA, integerINFO)

DPOTRF

Purpose:

DPOTRF computes the Cholesky factorization of a real symmetric
positive definite matrix A.

The factorization has the form
   A = U**T * U,  if UPLO = 'U', or
   A = L  * L**T,  if UPLO = 'L',
where U is an upper triangular matrix and L is lower triangular.

This is the block version of the algorithm, calling Level 3 BLAS.

Parameters:

UPLO

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

N

N is INTEGER
The order of the matrix A.  N >= 0.

A

A is DOUBLE PRECISION array, dimension (LDA,N)
On entry, the symmetric matrix A.  If UPLO = 'U', the leading
N-by-N upper triangular part of A contains the upper
triangular part of the matrix A, and the strictly lower
triangular part of A is not referenced.  If UPLO = 'L', the
leading N-by-N lower triangular part of A contains the lower
triangular part of the matrix A, and the strictly upper
triangular part of A is not referenced.

On exit, if INFO = 0, the factor U or L from the Cholesky
factorization A = U**T*U or A = L*L**T.

LDA

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

INFO

INFO is INTEGER
= 0:  successful exit
< 0:  if INFO = -i, the i-th argument had an illegal value
> 0:  if INFO = i, the leading minor of order i is not
      positive definite, and the factorization could not be
      completed.

Author:

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Date:

November 2011

Definition at line 108 of file dpotrf.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.

Referenced By

dpotrf(3) is an alias of dpotrf.f(3).

Sat Nov 16 2013 Version 3.4.2 LAPACK