ctrti2.f(3)

ctrti2.f3

Usage

Functions/Subroutines

subroutine ctrti2 (uplo, diag, n, a, lda, info)
CTRTI2 computes the inverse of a triangular matrix (unblocked algorithm).

Function/Subroutine Documentation

subroutine ctrti2 (character uplo, character diag, integer n, complex, dimension( lda, * ) a, integer lda, integer info)

CTRTI2 computes the inverse of a triangular matrix (unblocked algorithm).

Purpose:

!>
!> CTRTI2 computes the inverse of a complex upper or lower triangular
!> matrix.
!>
!> This is the Level 2 BLAS version of the algorithm.
!> 

Parameters

UPLO

!>          UPLO is CHARACTER*1
!>          Specifies whether the matrix A is upper or lower triangular.
!>          = 'U':  Upper triangular
!>          = 'L':  Lower triangular
!> 

DIAG

!>          DIAG is CHARACTER*1
!>          Specifies whether or not the matrix A is unit triangular.
!>          = 'N':  Non-unit triangular
!>          = 'U':  Unit triangular
!> 

N

!>          N is INTEGER
!>          The order of the matrix A.  N >= 0.
!> 

A

!>          A is COMPLEX array, dimension (LDA,N)
!>          On entry, the triangular matrix A.  If UPLO = 'U', the
!>          leading n by n upper triangular part of the array A contains
!>          the upper triangular matrix, and the strictly lower
!>          triangular part of A is not referenced.  If UPLO = 'L', the
!>          leading n by n lower triangular part of the array A contains
!>          the lower triangular matrix, and the strictly upper
!>          triangular part of A is not referenced.  If DIAG = 'U', the
!>          diagonal elements of A are also not referenced and are
!>          assumed to be 1.
!>
!>          On exit, the (triangular) inverse of the original matrix, in
!>          the same storage format.
!> 

LDA

!>          LDA is INTEGER
!>          The leading dimension of the array A.  LDA >= max(1,N).
!> 

INFO

!>          INFO is INTEGER
!>          = 0: successful exit
!>          < 0: if INFO = -k, the k-th argument had an illegal value
!> 

Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Definition at line 109 of file ctrti2.f.

Releases

4 releases since Debian 7 (Wheezy); the text changed 3 times.

  1. 7
  2. 8
  3. 9
  4. Arch

Author

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