root/library/tests/blas_test.cpp @ 550

#include <itpp/itbase.h>
using namespace itpp;

//These lines are needed for use of cout and endl
using std::cout;
using std::endl;

//#define NDEBUG

mat matmul ( mat &A, mat &B ) {
        mat C ( A.rows(), B.cols() );
        int i, j, k;
        double sum;

        for ( i = 0; i < A.rows(); i++ ) {
                for ( j = 0; j < A.cols(); j++ ) {
                        sum = 0.0;
                        for ( k = 0; k < A.cols(); k++ ) {
                                sum += A._elem ( i, k ) * B._elem ( k, j );
                        }
                        C ( i, j ) = sum;
                }
        }
        return C;
}

void matmul2 ( int n,  double *A, double *B, double *C ) {
        int i, j, k;
        double sum;

        for ( i = 0; i < n; i++ ) {
                for ( j = 0; j < n; j++ ) {
                        sum = 0.0;
                        for ( k = 0; k < n; k++ ) {
                                sum += A [ i*n+k ] * B [ k*n+j ];
                        }
                        C[ i*n+j] = sum;
                }
        }
//      return C;
}

int main() {
        Real_Timer tt;
        vec exec_times ( 4 );
        vec exec_times_b ( 4 );
        vec exec_times_c ( 4 );

        mat A;
        mat B;
        mat C;

        vec vn = "5 50 200 500";
        int n;

        for ( int i = 0; i < vn.length(); i++ ) {
                n = vn ( i );
                A = randu ( n, n );
                B = randu ( n, n );

                tt.tic();
                for ( int ii = 0; ii < 10; ii++ ) {
                        C = matmul ( A, B );
                }
                exec_times ( i ) = tt.toc();

                tt.tic();
                for ( int ii = 0; ii < 10; ii++ ) {
                        C = A * B;
                }
                exec_times_b ( i ) = tt.toc();

                C = zeros ( n, n );
                tt.tic();
                for ( int ii = 0; ii < 10; ii++ ) {
                        matmul2 ( n, A._data(), B._data(), C._data() );
                }
                exec_times_c ( i ) = tt.toc();
        }
        cout << exec_times << endl;
        cout << exec_times_b << endl;
        cout << exec_times_c << endl;

        it_file itf ( "blas_test.it" );
        itf << Name ( "exec_times" ) << exec_times;
        itf << Name ( "exec_times_b" ) << exec_times_b;
        itf << Name ( "exec_times_c" ) << exec_times_c;

        return 0;
}