static double *calc_inverse_improved( const double *src, const int size)
{
double *inverse = calc_inverse( src, size);
if( inverse)
{
double *err_mat = (double *)calloc( 2 * size * size, sizeof( double));
double *b_times_delta = err_mat + size * size;
int i;
#ifdef LSQUARE_ERROR
FILE *ofile = fopen( "lsquare.dat", "ab");
#endif
mult_matrices( err_mat, src, size, size, inverse, size);
for( i = 0; i < size; i++)
err_mat[i * (size + 1)] -= 1.;
#ifdef LSQUARE_ERROR
fprintf( ofile, "%d-square matrix delta (= AB - I):\n", size);
dump_matrix( ofile, err_mat, size);
fclose( ofile);
#endif
mult_matrices( b_times_delta, inverse, size, size, err_mat, size);
for( i = 0; i < size * size; i++)
inverse[i] -= b_times_delta[i];
free( err_mat);
}
return( inverse);
}
int main(int argc, char **argv)
{
if (argc != 2)
{
printf("Enter a file to be scanned.\n");
exit(0);
}
int *A, *B, *C;
int m, n, p;
read_matrices(&A, &B, &C, &m, &n, &p, *(argv+1));
mult_matrices(A, B, C, m, n, p);
printf("\nMatrix A contents:\n");
print_matrices(A, m, n);
printf("\nMatrix B contents:\n");
print_matrices(B, n, p);
printf("\nMatrix A * B is:\n");
print_matrices(C, m, p);
free(A);
free(B);
free(C);
exit(0);
}
/* {{{ check */
int check(matrix *m) {
int i, j;
REAL temp;
init_empty_matrix(&lower, m->rows, m->cols);
init_empty_matrix(&upper, m->rows, m->cols);
for (i=0; i<m->rows; i++) {
for (j=0; j<m->cols; j++) {
if (i>j) {
temp = GET(m,i,j);
SET(&lower,i,j,temp);
}
if (i<=j) {
temp = GET(m,i,j);
SET(&upper,i,j,temp);
}
}
SET(&lower,i,i,(REAL)1.0L);
}
mult_matrices(&mult, &lower, &upper);
if (dbg) {
printf("lower:\n");
print_matrix(&lower);
printf("upper:\n");
print_matrix(&upper);
printf("multiplied:\n");
print_matrix(&mult);
}
for (i=0; i<m->rows; i++) {
for (j=0; j<m->cols; j++) {
if (!EQUAL(GET(&mult,i,j),GET(&ref,i,j))) {
printf("(%d,%d): " FMT " != " FMT "\n",
i, j, GET(&mult,i,j), GET(&ref,i,j));
return EXIT_FAILURE;
}
}
}
return EXIT_SUCCESS;
} /* }}} */