ztptri


NAME

ztptri - compute the inverse of a complex upper or lower triangular matrix A stored in packed format


SYNOPSIS

  SUBROUTINE ZTPTRI( UPLO, DIAG, N, A, INFO)
  CHARACTER * 1 UPLO, DIAG
  DOUBLE COMPLEX A(*)
  INTEGER N, INFO
 
  SUBROUTINE ZTPTRI_64( UPLO, DIAG, N, A, INFO)
  CHARACTER * 1 UPLO, DIAG
  DOUBLE COMPLEX A(*)
  INTEGER*8 N, INFO
 

F95 INTERFACE

  SUBROUTINE TPTRI( UPLO, DIAG, N, A, [INFO])
  CHARACTER(LEN=1) :: UPLO, DIAG
  COMPLEX(8), DIMENSION(:) :: A
  INTEGER :: N, INFO
 
  SUBROUTINE TPTRI_64( UPLO, DIAG, N, A, [INFO])
  CHARACTER(LEN=1) :: UPLO, DIAG
  COMPLEX(8), DIMENSION(:) :: A
  INTEGER(8) :: N, INFO
 

C INTERFACE

#include <sunperf.h>

void ztptri(char uplo, char diag, int n, doublecomplex *a, int *info);

void ztptri_64(char uplo, char diag, long n, doublecomplex *a, long *info);


PURPOSE

ztptri computes the inverse of a complex upper or lower triangular matrix A stored in packed format.


ARGUMENTS

* UPLO (input)
* DIAG (input)

* N (input)
The order of the matrix A. N >= 0.

* A (input/output)
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.

* INFO (output)