Intel® oneAPI Math Kernel Library Developer Reference - C
Computes a matrix-matrix product with general matrices.
void cblas_hgemm (const CBLAS_LAYOUT Layout, const CBLAS_TRANSPOSE transa, const CBLAS_TRANSPOSE transb, const MKL_INT m, const MKL_INT n, const MKL_INT k, const MKL_F16 alpha, const MKL_F16 *a, const MKL_INT lda, const MKL_F16 *b, const MKL_INT ldb, const MKL_F16 beta, MKL_F16 *c, const MKL_INT ldc);
void cblas_sgemm (const CBLAS_LAYOUT Layout, const CBLAS_TRANSPOSE transa, const CBLAS_TRANSPOSE transb, const MKL_INT m, const MKL_INT n, const MKL_INT k, const float alpha, const float *a, const MKL_INT lda, const float *b, const MKL_INT ldb, const float beta, float *c, const MKL_INT ldc);
void cblas_dgemm (const CBLAS_LAYOUT Layout, const CBLAS_TRANSPOSE transa, const CBLAS_TRANSPOSE transb, const MKL_INT m, const MKL_INT n, const MKL_INT k, const double alpha, const double *a, const MKL_INT lda, const double *b, const MKL_INT ldb, const double beta, double *c, const MKL_INT ldc);
void cblas_cgemm (const CBLAS_LAYOUT Layout, const CBLAS_TRANSPOSE transa, const CBLAS_TRANSPOSE transb, const MKL_INT m, const MKL_INT n, const MKL_INT k, const void *alpha, const void *a, const MKL_INT lda, const void *b, const MKL_INT ldb, const void *beta, void *c, const MKL_INT ldc);
void cblas_zgemm (const CBLAS_LAYOUT Layout, const CBLAS_TRANSPOSE transa, const CBLAS_TRANSPOSE transb, const MKL_INT m, const MKL_INT n, const MKL_INT k, const void *alpha, const void *a, const MKL_INT lda, const void *b, const MKL_INT ldb, const void *beta, void *c, const MKL_INT ldc);
The ?gemm routines compute a scalar-matrix-matrix product and add the result to a scalar-matrix product, with general matrices. The operation is defined as
C := alpha*op(A)*op(B) + beta*C
where:
op(X) is one of op(X) = X, or op(X) = XT, or op(X) = XH,
alpha and beta are scalars,
A, B and C are matrices:
op(A) is an m-by-k matrix,
op(B) is a k-by-n matrix,
C is an m-by-n matrix.
See also:
?gemm for the Fortran language interface to this routine
?gemm3m, BLAS-like extension routines, that use matrix multiplication for similar matrix-matrix operations
Specifies whether two-dimensional array storage is row-major (CblasRowMajor) or column-major (CblasColMajor).
Specifies the form of op(A) used in the matrix multiplication:
if transa=CblasNoTrans, then op(A) = A;
if transa=CblasTrans, then op(A) = AT;
if transa=CblasConjTrans, then op(A) = AH.
Specifies the form of op(B) used in the matrix multiplication:
if transb=CblasNoTrans, then op(B) = B;
if transb=CblasTrans, then op(B) = BT;
if transb=CblasConjTrans, then op(B) = BH.
Specifies the number of rows of the matrix op(A) and of the matrix C. The value of m must be at least zero.
Specifies the number of columns of the matrix op(B) and the number of columns of the matrix C. The value of n must be at least zero.
Specifies the number of columns of the matrix op(A) and the number of rows of the matrix op(B). The value of k must be at least zero.
Specifies the scalar alpha.
transa=CblasNoTrans |
transa=CblasTrans or transa=CblasConjTrans |
|
Layout = CblasColMajor |
Array, size lda*k. Before entry, the leading m-by-k part of the array a must contain the matrix A. |
Array, size lda*m. Before entry, the leading k-by-m part of the array a must contain the matrix A. |
Layout = CblasRowMajor |
Array, size lda* m. Before entry, the leading k-by-m part of the array a must contain the matrix A. |
Array, size lda*k. Before entry, the leading m-by-k part of the array a must contain the matrix A. |
Specifies the leading dimension of a as declared in the calling (sub)program.
transa=CblasNoTrans |
transa=CblasTrans or transa=CblasConjTrans |
|
Layout = CblasColMajor |
lda must be at least max(1, m). |
lda must be at least max(1, k) |
Layout = CblasRowMajor |
lda must be at least max(1, k) |
lda must be at least max(1, m). |
transb=CblasNoTrans |
transb=CblasTrans or transb=CblasConjTrans |
|
Layout = CblasColMajor |
Array, size ldb by n. Before entry, the leading k-by-n part of the array b must contain the matrix B. |
Array, size ldb by k. Before entry the leading n-by-k part of the array b must contain the matrix B. |
Layout = CblasRowMajor |
Array, size ldb by k. Before entry the leading n-by-k part of the array b must contain the matrix B. |
Array, size ldb by n. Before entry, the leading k-by-n part of the array b must contain the matrix B. |
Specifies the leading dimension of b as declared in the calling (sub)program.
When transb=CblasNoTrans , then ldb must be at least max(1, k), otherwise ldb must be at least max(1, n).
transb=CblasNoTrans |
transb=CblasTrans or transb=CblasConjTrans |
|
Layout = CblasColMajor |
ldb must be at least max(1, k). |
ldb must be at least max(1, n). |
Layout = CblasRowMajor |
ldb must be at least max(1, n). |
ldb must be at least max(1, k). |
Specifies the scalar beta. When beta is equal to zero, then c need not be set on input.
Layout = CblasColMajor |
Array, size ldc by n. Before entry, the leading m-by-n part of the array c must contain the matrix C, except when beta is equal to zero, in which case c need not be set on entry. |
Layout = CblasRowMajor |
Array, size ldc by m. Before entry, the leading n-by-m part of the array c must contain the matrix C, except when beta is equal to zero, in which case c need not be set on entry. |
Specifies the leading dimension of c as declared in the calling (sub)program.
Layout = CblasColMajor |
ldc must be at least max(1, m). |
Layout = CblasRowMajor |
ldc must be at least max(1, n). |
Overwritten by the m-by-n matrix (alpha*op(A)*op(B) + beta*C).
For examples of routine usage, see these code examples in the Intel® oneAPI Math Kernel Library installation directory:
cblas_hgemm: examples\cblas\source\cblas_hgemmx.c
cblas_sgemm: examples\cblas\source\cblas_sgemmx.c
cblas_dgemm: examples\cblas\source\cblas_dgemmx.c
cblas_cgemm: examples\cblas\source\cblas_cgemmx.c
cblas_zgemm: examples\cblas\source\cblas_zgemmx.c