Function stackCSRColumn

XM/include/Sparse/stack.h:12–31

Function to stack CSR matrices in a column This function stacks two CSR matrices in a column The output matrix is the concatenation of the two input matrices The output matrix is stored in CSR format C = [alpha*A; beta*B]

// The output matrix is stored in CSR format
// C = [alpha*A; beta*B]
__global__ void stackCSRColumn(const int* row_ptr1, const int* col_ind1, const double* values1, int nnz1,
                               const int* row_ptr2, const int* col_ind2, const double* values2, int nnz2,
                               int* row_ptr_out, int* col_ind_out, double* values_out, int num_rows1, int num_rows2,
                               double alpha, double beta){
    int i = blockIdx.x * blockDim.x + threadIdx.x;
    if(i < nnz1){
        col_ind_out[i] = col_ind1[i];
        values_out[i] = alpha * values1[i];
    }
    if(i < nnz2){
        col_ind_out[i + nnz1] = col_ind2[i];
        values_out[i + nnz1] = beta * values2[i];
    }
    if(i < num_rows1){
        row_ptr_out[i] = row_ptr1[i];
    }
    if(i < num_rows2){
        row_ptr_out[i + num_rows1] = row_ptr2[i] + nnz1;
    }
}

// Function to stack CSR matrices in a row
// This function stacks two CSR matrices in a row