zpotf2.f man page

zpotf2.f

Synopsis

Functions/Subroutines

subroutine zpotf2 (UPLO, N, A, LDA, INFO)
ZPOTF2 computes the Cholesky factorization of a symmetric/Hermitian positive definite matrix (unblocked algorithm).

Function/Subroutine Documentation

subroutine zpotf2 (character UPLO, integer N, complex*16, dimension( lda, * ) A, integer LDA, integer INFO)

ZPOTF2 computes the Cholesky factorization of a symmetric/Hermitian positive definite matrix (unblocked algorithm).  

Purpose:

 ZPOTF2 computes the Cholesky factorization of a complex Hermitian
 positive definite matrix A.

 The factorization has the form
    A = U**H * U ,  if UPLO = 'U', or
    A = L  * L**H,  if UPLO = 'L',
 where U is an upper triangular matrix and L is lower triangular.

 This is the unblocked version of the algorithm, calling Level 2 BLAS.
Parameters:

UPLO

          UPLO is CHARACTER*1
          Specifies whether the upper or lower triangular part of the
          Hermitian matrix A is stored.
          = 'U':  Upper triangular
          = 'L':  Lower triangular

N

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

A

          A is COMPLEX*16 array, dimension (LDA,N)
          On entry, the Hermitian 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**H *U  or A = L*L**H.

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 = -k, the k-th argument had an illegal value
          > 0: if INFO = k, the leading minor of order k 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:

December 2016

Definition at line 111 of file zpotf2.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.

Referenced By

The man page zpotf2(3) is an alias of zpotf2.f(3).

Tue Nov 14 2017 Version 3.8.0 LAPACK