CPOTRF(l) LAPACK routine (version 1.1) CPOTRF(l)
NAME
CPOTRF - compute the Cholesky factorization of a complex Hermitian positive
definite matrix A
SYNOPSIS
SUBROUTINE CPOTRF( UPLO, N, A, LDA, INFO )
CHARACTER UPLO
INTEGER INFO, LDA, N
COMPLEX A( LDA, * )
PURPOSE
CPOTRF 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 block version of the algorithm, calling Level 3 BLAS.
ARGUMENTS
UPLO (input) CHARACTER*1
= 'U': Upper triangle of A is stored;
= 'L': Lower triangle of A is stored.
N (input) INTEGER
The order of the matrix A. N >= 0.
A (input/output) COMPLEX 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 factori-
zation A = U**H*U or A = L*L**H.
LDA (input) INTEGER
The leading dimension of the array A. LDA >= max(1,N).
INFO (output) 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.
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