Developer Reference for Intel® oneAPI Math Kernel Library for C
?trsm
Solves a triangular matrix equation.
Syntax
void cblas_strsm(const CBLAS_LAYOUT Layout, const CBLAS_SIDE side, const CBLAS_UPLO uplo,
const CBLAS_TRANSPOSE transa, const CBLAS_DIAG diag, const MKL_INT m,
const MKL_INT n, const float alpha, const float *a, const MKL_INT lda,
float *b, const MKL_INT ldb);
void cblas_dtrsm(const CBLAS_LAYOUT Layout, const CBLAS_SIDE side, const CBLAS_UPLO uplo,
const CBLAS_TRANSPOSE transa, const CBLAS_DIAG diag, const MKL_INT m,
const MKL_INT n, const double alpha, const double *a, const MKL_INT lda,
double *b, const MKL_INT ldb);
void cblas_ctrsm(const CBLAS_LAYOUT Layout, const CBLAS_SIDE side, const CBLAS_UPLO uplo,
const CBLAS_TRANSPOSE transa, const CBLAS_DIAG diag, const MKL_INT m,
const MKL_INT n, const void *alpha, const void *a, const MKL_INT lda,
void *b, const MKL_INT ldb);
void cblas_ztrsm(const CBLAS_LAYOUT Layout, const CBLAS_SIDE side, const CBLAS_UPLO uplo,
const CBLAS_TRANSPOSE transa, const CBLAS_DIAG diag, const MKL_INT m,
const MKL_INT n, const void *alpha, const void *a, const MKL_INT lda,
void *b, const MKL_INT ldb);Include Files
mkl.h
Description
The ?trsm routines solve one of the following matrix equations: op( A )* X = alpha * B ,
or X *op( A ) = alpha * B ,
where:
alpha is a scalar,
X and B are m -by- n matrices,
A is a unit, or non-unit, upper or lower triangular matrix, and
op(A) is one of op(A) = A , or op(A) = A' , or op(A) = conjg(A') .
The matrix B is overwritten by the solution matrix X .
Input Parameters
- Layout
-
Specifies whether two-dimensional array storage is row-major ( CblasRowMajor ) or column-major ( CblasColMajor ).
side
Specifies whether op(A) appears on the left or right of X in the equation:
if side = CblasLeft , then op(A)*X = alpha*B ;
if side = CblasRight , then X*op(A) = alpha*B .
uplo
Specifies whether the matrix A is upper or lower triangular.
if uplo = CblasLower , then the matrix is low triangular.
transa
Specifies the form of op(A) used in the matrix multiplication:
if transa = CblasNoTrans , then op(A) = A ;
if transa = CblasTrans ;
if transa = CblasConjTrans , then op(A) = conjg(A') .
diag
Specifies whether the matrix A is unit triangular:
if diag = CblasUnit then the matrix is unit triangular;
if diag = CblasNonUnit , then the matrix is not unit triangular.
- m
-
Specifies the number of rows of B . The value of m must be at least zero.
- n
-
Specifies the number of columns of B . The value of n must be at least zero.
- alpha
-
REAL for strsm DOUBLE PRECISION for dtrsm COMPLEX for ctrsm DOUBLE COMPLEX for ztrsm Specifies the scalar alpha . When alpha is zero, then a is not referenced and b need not be set before entry.
- a
-
REAL for strsm DOUBLE PRECISION for dtrsm COMPLEX for ctrsm DOUBLE COMPLEX for ztrsm
Array, size (lda, k)lda* k , where k is m when side = CblasLeft and is n when side = CblasRight . Before entry with uplo = CblasUpper , the leading k by k upper triangular part of the array a must contain the upper triangular matrix and the strictly lower triangular part of a is not referenced.
Before entry with uplo = CblasLower lower triangular part of the array a must contain the lower triangular matrix and the strictly upper triangular part of a is not referenced.
When diag = CblasUnit , the diagonal elements of a are not referenced either, but are assumed to be unity.
lda
Specifies the leading dimension of a as declared in the calling (sub)program. When side = CblasLeft , then lda must be at least max(1, m) , when side = CblasRight , then lda must be at least max(1, n) .
- b
-
REAL for strsm DOUBLE PRECISION for dtrsm COMPLEX for ctrsm DOUBLE COMPLEX for ztrsm Array, size ldb by n . Before entry, the leading m -by- n part of the array b must contain the matrix B . For Layout = CblasColMajor : array, size ldb*n . Before entry, the leading m -by- n part of the array b must contain the matrix B . For Layout = CblasRowMajor : array, size ldb*m . Before entry, the leading n -by- m part of the array b must contain the matrix B .
ldb
Specifies the leading dimension of b as declared in the calling (sub)program. When Layout = CblasColMajor , ldb must be at least max(1, m) ; otherwise, ldb must be at least max(1, n) .
Output Parameters
- b
-
Overwritten by the solution matrix X .
BLAS 95 Interface Notes
There exist FORTRAN 77 and FORTRAN 95 interfaces for this routine. See the Intel® oneMKL Fortran Developer Reference for details.