Developer Reference for Intel® oneAPI Math Kernel Library for C
?gemm_batch
Computes scalar-matrix-matrix products and adds the results to scalar matrix products for groups of general matrices.
Syntax
void cblas_sgemm_batch(const CBLAS_LAYOUT Layout, const CBLAS_TRANSPOSE *transa_array,
const CBLAS_TRANSPOSE *transb_array, const MKL_INT *m_array,
const MKL_INT *n_array, const MKL_INT *k_array, const float *alpha_array,
const float **a_array, const MKL_INT *lda_array, const float **b_array,
const MKL_INT *ldb_array, const float *beta_array, float **c_array,
const MKL_INT *ldc_array, const MKL_INT group_count,
const MKL_INT *group_size);
void cblas_dgemm_batch(const CBLAS_LAYOUT Layout, const CBLAS_TRANSPOSE *transa_array,
const CBLAS_TRANSPOSE *transb_array, const MKL_INT *m_array,
const MKL_INT *n_array, const MKL_INT *k_array, const double *alpha_array,
const double **a_array, const MKL_INT *lda_array, const double **b_array,
const MKL_INT *ldb_array, const double *beta_array, double **c_array,
const MKL_INT *ldc_array, const MKL_INT group_count,
const MKL_INT *group_size);
void cblas_cgemm_batch(const CBLAS_LAYOUT Layout, const CBLAS_TRANSPOSE *transa_array,
const CBLAS_TRANSPOSE *transb_array, const MKL_INT *m_array,
const MKL_INT *n_array, const MKL_INT *k_array, const void *alpha_array,
const void **a_array, const MKL_INT *lda_array, const void **b_array,
const MKL_INT *ldb_array, const void *beta_array, void **c_array,
const MKL_INT *ldc_array, const MKL_INT group_count,
const MKL_INT *group_size);
void cblas_zgemm_batch(const CBLAS_LAYOUT Layout, const CBLAS_TRANSPOSE *transa_array,
const CBLAS_TRANSPOSE *transb_array, const MKL_INT *m_array,
const MKL_INT *n_array, const MKL_INT *k_array, const void *alpha_array,
const void **a_array, const MKL_INT *lda_array, const void **b_array,
const MKL_INT *ldb_array, const void *beta_array, void **c_array,
const MKL_INT *ldc_array, const MKL_INT group_count,
const MKL_INT *group_size);Include Files
mkl.h
Description
The ?gemm_batch routines perform a series of matrix-matrix operations with general matrices. They are similar to the ?gemm routine counterparts, but the ?gemm_batch routines perform matrix-matrix operations with groups of matrices , processing a number of groups at once . The groups contain matrices with the same parameters.
The operation is defined as
idx = 0
for i = 0..group_count - 1
alpha and beta in alpha_array[i] and beta_array[i]
for j = 0..group_size[i] - 1
A, B, and C matrix in a_array[idx], b_array[idx], and c_array[idx]
C := alpha*op(A)*op(B) + beta*C, idx = idx + 1
end for
end forwhere:
op(X) is one of op(X) = X , or op(X) = X^{T} , or op(X) = X^{H} ,
alpha and beta are scalar elements of alpha_array and beta_array ,
A , B and C are matrices such that for m , n , and k which are elements of m_array , n_array , and k_array :
op(A) is an m -by- k matrix,
op(B) is a k -by- n matrix,
C is an m -by- n matrix.
A , B , and C represent matrices stored at addresses pointed to by a_array , b_array , and c_array , respectively. The number of entries in a_array , b_array , and c_array is total_batch_count = the sum of all of the group_size entries.
See also gemm for a detailed description of multiplication for general matrices and ?gemm3m_batch , BLAS-like extension routines for similar matrix-matrix operations.
Input Parameters
- Layout
- Specifies whether two-dimensional array storage is row-major ( CblasRowMajor ) or column-major ( CblasColMajor ).
- transa_array
-
Array of size group_count . For the group i , transa_{i} = transa_array(i)[i] specifies the form of op(A) used in the matrix multiplication:
if transai = CblasNoTrans , then op(A) = A ;
if transai = CblasTrans , then op(A) = A^{T} ;
if transai = CblasConjTrans , then op(A) = A^{H} .
- transb_array
-
Array of size group_count . For the group i , transb_{i} = transb_array(i)[i] specifies the form of op(B_{i}) used in the matrix multiplication:
if transbi = CblasNoTrans , then op(B) = B ;
if transbi = CblasTrans , then op(B) = B^{T} ;
if transbi = CblasConjTrans , then op(B) = B^{H} .
- m_array
-
Array of size group_count . For the group i , mi = m_array(i)[i] specifies the number of rows of the matrix op(A) and of the matrix C .
The value of each element of m_array must be at least zero.
- n_array
-
Array of size group_count . For the group i , ni = n_array(i)[i] specifies the number of columns of the matrix op(B) and the number of columns of the matrix C .
The value of each element of n_array must be at least zero.
- k_array
-
Array of size group_count . For the group i , ki = k_array(i)[i] specifies the number of columns of the matrix op(A) and the number of rows of the matrix op(B) .
The value of each element of k_array must be at least zero.
- alpha_array
-
REAL for sgemm_batch DOUBLE PRECISION for dgemm_batch COMPLEX for cgemm_batch DOUBLE COMPLEX for zgemm_batch Array of size group_count . For the group i , alpha_array(i)[i] specifies the scalar alphai .
- a_array
-
INTEGER*8 for Intel ® 64 architecture Array, size total_batch_count , of pointers to arrays used to store A matrices.
- lda_array
-
Array of size group_count . For the group i , lda_{i} =lda_array(i)lda_array[i] specifies the leading dimension of the array storing matrix A as declared in the calling (sub)program.
When transa_{i} ='N' or 'n' , then ldai must be at least max(1, m_{i}) , otherwise ldai must be at least max(1, k_{i}) .
- b_array
-
INTEGER*8 for Intel ® 64 architecture Array, size total_batch_count , of pointers to arrays used to store B matrices.
- ldb_array
-
INTEGER . Array of size group_count . For the group i , ldb_{i} = ldb_array(i)[i] specifies the leading dimension of the array storing matrix B as declared in the calling (sub)program. When transb_{i} = 'N' or 'n' , then ldbi must be at least max(1, k_{i}) , otherwise ldbi must be at least max(1, n_{i}) .
- beta_array
-
REAL for sgemm_batch DOUBLE PRECISION for dgemm_batch COMPLEX for cgemm_batch DOUBLE COMPLEX for zgemm_batch Array of size group_count . For the group i , beta_array(i)[i] specifies the scalar betai . When betai is equal to zero, then C matrices in group i need not be set on input.
- c_array
-
INTEGER*8 for Intel ® 64 architecture Array, size total_batch_count , of pointers to arrays used to store C matrices.
- ldc_array
-
INTEGER . Array of size group_count . For the group i , ldc_{i} = ldc_array(i)[i] specifies the leading dimension of all arrays storing matrix C in group i as declared in the calling (sub)program.
When Layout = CblasColMajorldci must be at least max(1, m_{i}) .
When Layout = CblasRowMajorldci must be at least max(1, n_{i}) .
- group_count
-
INTEGER . Specifies the number of groups. Must be at least 0.
- group_size
-
INTEGER . Array of size group_count . The element group_size(i)[i] specifies the number of matrices in group i . Each element in group_size must be at least 0.
Output Parameters
- c_array
-
Output buffer, overwritten by total_batch_count matrix multiply operations of the form alpha*op(A)*op(B) + beta*C .
BLAS 95 Interface Notes
There exist FORTRAN 77 and FORTRAN 95 interfaces for this routine. See the Intel® oneMKL Fortran Developer Reference for details.