spotf2 - compute the Cholesky factorization of a real symmetric positive definite matrix A
SUBROUTINE SPOTF2( UPLO, N, A, LDA, INFO) CHARACTER * 1 UPLO INTEGER N, LDA, INFO REAL A(LDA,*)
SUBROUTINE SPOTF2_64( UPLO, N, A, LDA, INFO) CHARACTER * 1 UPLO INTEGER*8 N, LDA, INFO REAL A(LDA,*)
SUBROUTINE POTF2( UPLO, [N], A, [LDA], [INFO]) CHARACTER(LEN=1) :: UPLO INTEGER :: N, LDA, INFO REAL, DIMENSION(:,:) :: A
SUBROUTINE POTF2_64( UPLO, [N], A, [LDA], [INFO]) CHARACTER(LEN=1) :: UPLO INTEGER(8) :: N, LDA, INFO REAL, DIMENSION(:,:) :: A
#include <sunperf.h>
void spotf2(char uplo, int n, float *a, int lda, int *info);
void spotf2_64(char uplo, long n, float *a, long lda, long *info);
spotf2 computes the Cholesky factorization of a real symmetric positive definite matrix A.
The factorization has the form
A = U' * U , if UPLO = 'U', or
A = L * L', 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.
= 'L': Lower triangular
On exit, if INFO = 0, the factor U or L from the Cholesky factorization A = U'*U or A = L*L'.
= 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.