/* Tridiagonals solvers */
void solve_tridiag_qr(int n, double *D, double *E, char type){ if (type == 'N'){
printf("Using PWK variant\n");
int info = LAPACKE_dsterf(n, D, E);
assert(!info);
}
else {
double *Q = malloc(n*n*sizeof(double)); assert(Q);
int info = LAPACKE_dsteqr(LAPACK_COL_MAJOR, type, n, D, E, Q, n);
assert(!info);
free(Q);
}
}
int main(void)
{
/* Local scalars */
lapack_int n, n_i;
lapack_int info, info_i;
lapack_int i;
int failed;
/* Local arrays */
double *d = NULL, *d_i = NULL;
double *e = NULL, *e_i = NULL;
double *d_save = NULL;
double *e_save = NULL;
/* Iniitialize the scalar parameters */
init_scalars_dsterf( &n );
n_i = n;
/* Allocate memory for the LAPACK routine arrays */
d = (double *)LAPACKE_malloc( n * sizeof(double) );
e = (double *)LAPACKE_malloc( (n-1) * sizeof(double) );
/* Allocate memory for the C interface function arrays */
d_i = (double *)LAPACKE_malloc( n * sizeof(double) );
e_i = (double *)LAPACKE_malloc( (n-1) * sizeof(double) );
/* Allocate memory for the backup arrays */
d_save = (double *)LAPACKE_malloc( n * sizeof(double) );
e_save = (double *)LAPACKE_malloc( (n-1) * sizeof(double) );
/* Allocate memory for the row-major arrays */
/* Initialize input arrays */
init_d( n, d );
init_e( (n-1), e );
/* Backup the ouptut arrays */
for( i = 0; i < n; i++ ) {
d_save[i] = d[i];
}
for( i = 0; i < (n-1); i++ ) {
e_save[i] = e[i];
}
/* Call the LAPACK routine */
dsterf_( &n, d, e, &info );
/* Initialize input data, call the column-major middle-level
* interface to LAPACK routine and check the results */
for( i = 0; i < n; i++ ) {
d_i[i] = d_save[i];
}
for( i = 0; i < (n-1); i++ ) {
e_i[i] = e_save[i];
}
info_i = LAPACKE_dsterf_work( n_i, d_i, e_i );
failed = compare_dsterf( d, d_i, e, e_i, info, info_i, n );
if( failed == 0 ) {
printf( "PASSED: column-major middle-level interface to dsterf\n" );
} else {
printf( "FAILED: column-major middle-level interface to dsterf\n" );
}
/* Initialize input data, call the column-major high-level
* interface to LAPACK routine and check the results */
for( i = 0; i < n; i++ ) {
d_i[i] = d_save[i];
}
for( i = 0; i < (n-1); i++ ) {
e_i[i] = e_save[i];
}
info_i = LAPACKE_dsterf( n_i, d_i, e_i );
failed = compare_dsterf( d, d_i, e, e_i, info, info_i, n );
if( failed == 0 ) {
printf( "PASSED: column-major high-level interface to dsterf\n" );
} else {
printf( "FAILED: column-major high-level interface to dsterf\n" );
}
failed = compare_dsterf( d, d_i, e, e_i, info, info_i, n );
if( failed == 0 ) {
printf( "PASSED: row-major middle-level interface to dsterf\n" );
} else {
printf( "FAILED: row-major middle-level interface to dsterf\n" );
}
failed = compare_dsterf( d, d_i, e, e_i, info, info_i, n );
if( failed == 0 ) {
printf( "PASSED: row-major high-level interface to dsterf\n" );
} else {
printf( "FAILED: row-major high-level interface to dsterf\n" );
}
/* Release memory */
if( d != NULL ) {
LAPACKE_free( d );
}
if( d_i != NULL ) {
LAPACKE_free( d_i );
}
if( d_save != NULL ) {
LAPACKE_free( d_save );
}
if( e != NULL ) {
LAPACKE_free( e );
}
if( e_i != NULL ) {
LAPACKE_free( e_i );
}
if( e_save != NULL ) {
LAPACKE_free( e_save );
}
return 0;
}