Visible to Intel only — GUID: GUID-68BEC94A-C804-4EF3-9729-7C277EBFFF10
Visible to Intel only — GUID: GUID-68BEC94A-C804-4EF3-9729-7C277EBFFF10
?trti2
Computes the inverse of a triangular matrix (unblocked algorithm).
Syntax
call strti2( uplo, diag, n, a, lda, info )
call dtrti2( uplo, diag, n, a, lda, info )
call ctrti2( uplo, diag, n, a, lda, info )
call ztrti2( uplo, diag, n, a, lda, info )
Include Files
- mkl.fi
Description
The routine ?trti2 computes the inverse of a real/complex upper or lower triangular matrix.
This is the Level 2 BLAS version of the algorithm.
Input Parameters
- uplo
-
CHARACTER*1.
Specifies whether the matrix A is upper or lower triangular.
= 'U': upper triangular
= 'L': lower triangular
- diag
-
CHARACTER*1.
Specifies whether or not the matrix A is unit triangular.
= 'N': non-unit triangular
= 'N': non-unit triangular
- n
-
INTEGER. The order of the matrix A. n≥ 0.
- a
-
REAL for strti2
DOUBLE PRECISION for dtrti2
COMPLEX for ctrti2
DOUBLE COMPLEX for ztrti2.
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.
- lda
-
INTEGER. The leading dimension of the array a. lda≥ max(1,n).
Output Parameters
- a
-
On exit, the (triangular) inverse of the original matrix, in the same storage format.
- info
-
INTEGER.
= 0: successful exit
< 0: if info = -k, the k-th argument had an illegal value