dtptri
dtptri - compute the inverse of a real upper or lower triangular matrix A stored in packed format
SUBROUTINE DTPTRI( UPLO, DIAG, N, A, INFO)
CHARACTER * 1 UPLO, DIAG
INTEGER N, INFO
DOUBLE PRECISION A(*)
SUBROUTINE DTPTRI_64( UPLO, DIAG, N, A, INFO)
CHARACTER * 1 UPLO, DIAG
INTEGER*8 N, INFO
DOUBLE PRECISION A(*)
SUBROUTINE TPTRI( UPLO, DIAG, N, A, [INFO])
CHARACTER(LEN=1) :: UPLO, DIAG
INTEGER :: N, INFO
REAL(8), DIMENSION(:) :: A
SUBROUTINE TPTRI_64( UPLO, DIAG, N, A, [INFO])
CHARACTER(LEN=1) :: UPLO, DIAG
INTEGER(8) :: N, INFO
REAL(8), DIMENSION(:) :: A
#include <sunperf.h>
void dtptri(char uplo, char diag, int n, double *a, int *info);
void dtptri_64(char uplo, char diag, long n, double *a, long *info);
dtptri computes the inverse of a real upper or lower triangular
matrix A stored in packed format.
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* UPLO (input)
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* DIAG (input)
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* N (input)
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The order of the matrix A. N >= 0.
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* A (input/output)
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On entry, the upper or lower triangular matrix A, stored
columnwise in a linear array. The j-th column of A is stored
in the array A as follows:
if UPLO = 'U', A(i + (j-1)*j/2) = A(i,j) for 1<=i<=j;
if UPLO = 'L', A(i + (j-1)*((2*n-j)/2) = A(i,j) for j<=i<=n.
See below for further details.
On exit, the (triangular) inverse of the original matrix, in
the same packed storage format.
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* INFO (output)
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