Contents
zpotri - compute the inverse of a complex Hermitian positive
definite matrix A using the Cholesky factorization A =
U**H*U or A = L*L**H computed by ZPOTRF
SUBROUTINE ZPOTRI(UPLO, N, A, LDA, INFO)
CHARACTER * 1 UPLO
DOUBLE COMPLEX A(LDA,*)
INTEGER N, LDA, INFO
SUBROUTINE ZPOTRI_64(UPLO, N, A, LDA, INFO)
CHARACTER * 1 UPLO
DOUBLE COMPLEX A(LDA,*)
INTEGER*8 N, LDA, INFO
F95 INTERFACE
SUBROUTINE POTRI(UPLO, [N], A, [LDA], [INFO])
CHARACTER(LEN=1) :: UPLO
COMPLEX(8), DIMENSION(:,:) :: A
INTEGER :: N, LDA, INFO
SUBROUTINE POTRI_64(UPLO, [N], A, [LDA], [INFO])
CHARACTER(LEN=1) :: UPLO
COMPLEX(8), DIMENSION(:,:) :: A
INTEGER(8) :: N, LDA, INFO
C INTERFACE
#include <sunperf.h>
void zpotri(char uplo, int n, doublecomplex *a, int lda, int
*info);
void zpotri_64(char uplo, long n, doublecomplex *a, long
lda, long *info);
zpotri computes the inverse of a complex Hermitian positive
definite matrix A using the Cholesky factorization A =
U**H*U or A = L*L**H computed by ZPOTRF.
UPLO (input)
= 'U': Upper triangle of A is stored;
= 'L': Lower triangle of A is stored.
N (input) The order of the matrix A. N >= 0.
A (input/output)
On entry, the triangular factor U or L from the
Cholesky factorization A = U**H*U or A = L*L**H,
as computed by ZPOTRF. On exit, the upper or
lower triangle of the (Hermitian) inverse of A,
overwriting the input factor U or L.
LDA (input)
The leading dimension of the array A. LDA >=
max(1,N).
INFO (output)
= 0: successful exit
< 0: if INFO = -i, the i-th argument had an ille-
gal value
> 0: if INFO = i, the (i,i) element of the factor
U or L is zero, and the inverse could not be com-
puted.