p?trti2
p?trti2
Computes the inverse of a triangular matrix (local unblocked algorithm).
Syntax
void
pstrti2
(
char
*uplo
,
char
*diag
,
MKL_INT
*n
,
float
*a
,
MKL_INT
*ia
,
MKL_INT
*ja
,
MKL_INT
*desca
,
MKL_INT
*info
);
void
pdtrti2
(
char
*uplo
,
char
*diag
,
MKL_INT
*n
,
double
*a
,
MKL_INT
*ia
,
MKL_INT
*ja
,
MKL_INT
*desca
,
MKL_INT
*info
);
void
pctrti2
(
char
*uplo
,
char
*diag
,
MKL_INT
*n
,
MKL_Complex8
*a
,
MKL_INT
*ia
,
MKL_INT
*ja
,
MKL_INT
*desca
,
MKL_INT
*info
);
void
pztrti2
(
char
*uplo
,
char
*diag
,
MKL_INT
*n
,
MKL_Complex16
*a
,
MKL_INT
*ia
,
MKL_INT
*ja
,
MKL_INT
*desca
,
MKL_INT
*info
);
Include Files
- mkl_scalapack.h
Description
The .
p?trti2
function
computes the inverse of a real/complex upper or lower triangular block matrix sub (
, A
) = A
(ia
:ia
+n
-1ja
:ja
+n
-1)This matrix should be contained in one and only one process memory space (local operation).
Input Parameters
- uplo
- (global)Specifies whether the matrix sub (A) is upper or lower triangular.='U': sub (A) is upper triangular='L': sub (A) is lower triangular.
- diag
- (global)Specifies whether or not the matrixAis unit triangular.='N': sub (A) is non-unit triangular='U': sub (A) is unit triangular.
- n
- (global)The number of rows and columns to be operated on, i.e., the order of the distributed submatrixsub(.A).n≥0
- a
- (local)Pointer into the local memory to an array,size.*lld_aLOCc(ja+n-1)On entry, this array contains the local pieces of the triangular matrix sub(A).If, the leadinguplo='U'n-by-nupper triangular part of the matrix sub(A) contains the upper triangular part of the matrix, and the strictly lower triangular part of sub(A) is not referenced.If, the leadinguplo='L'n-by-nlower triangular part of the matrix sub(A) contains the lower triangular part of the matrix, and the strictly upper triangular part of sub(A) is not referenced. If, the diagonal elements of sub(diag='U'A) are not referenced either and are assumed to be 1.
- ia,ja
- (global)The row and column indices in the global matrixAindicating the first row and the first column of the sub(A), respectively.
- desca
- (global and local) array of sizedlen_. The array descriptor for the distributed matrixA.
Output Parameters
- a
- On exit, the (triangular) inverse of the original matrix, in the same storage format.
- info
- = 0: successful exit< 0: if thei-th argument is an array and thej-th entry, indexedhad an illegal value,j-1,theninfo= - (i*100+j),if thei-th argument is a scalar and had an illegal value,theninfo= -i.