dgbrfs_1.c

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/*  Contents: test routine for C interface to LAPACK
*   Author: Intel Corporation
*   Created in March, 2010
*
* Purpose
*
* dgbrfs_1 is the test program for the C interface to LAPACK
* routine dgbrfs
* The program doesn't require an input, the input data is hardcoded in the
* test program.
* The program tests the C interface in the four combinations:
*   1) column-major layout, middle-level interface
*   2) column-major layout, high-level interface
*   3) row-major layout, middle-level interface
*   4) row-major layout, high-level interface
* The output of the C interface function is compared to those obtained from
* the corresponiding LAPACK routine with the same input data, and the
* comparison diagnostics is then printed on the standard output having PASSED
* keyword if the test is passed, and FAILED keyword if the test isn't passed.
*****************************************************************************/
#include <stdio.h>
#include "lapacke.h"
#include "lapacke_utils.h"
#include "test_utils.h"

static void init_scalars_dgbrfs( char *trans, lapack_int *n, lapack_int *kl,
                                 lapack_int *ku, lapack_int *nrhs,
                                 lapack_int *ldab, lapack_int *ldafb,
                                 lapack_int *ldb, lapack_int *ldx );
static void init_ab( lapack_int size, double *ab );
static void init_afb( lapack_int size, double *afb );
static void init_ipiv( lapack_int size, lapack_int *ipiv );
static void init_b( lapack_int size, double *b );
static void init_x( lapack_int size, double *x );
static void init_ferr( lapack_int size, double *ferr );
static void init_berr( lapack_int size, double *berr );
static void init_work( lapack_int size, double *work );
static void init_iwork( lapack_int size, lapack_int *iwork );
static int compare_dgbrfs( double *x, double *x_i, double *ferr, double *ferr_i,
                           double *berr, double *berr_i, lapack_int info,
                           lapack_int info_i, lapack_int ldx, lapack_int nrhs );

int main(void)
{
    /* Local scalars */
    char trans, trans_i;
    lapack_int n, n_i;
    lapack_int kl, kl_i;
    lapack_int ku, ku_i;
    lapack_int nrhs, nrhs_i;
    lapack_int ldab, ldab_i;
    lapack_int ldab_r;
    lapack_int ldafb, ldafb_i;
    lapack_int ldafb_r;
    lapack_int ldb, ldb_i;
    lapack_int ldb_r;
    lapack_int ldx, ldx_i;
    lapack_int ldx_r;
    lapack_int info, info_i;
    lapack_int i;
    int failed;

    /* Local arrays */
    double *ab = NULL, *ab_i = NULL;
    double *afb = NULL, *afb_i = NULL;
    lapack_int *ipiv = NULL, *ipiv_i = NULL;
    double *b = NULL, *b_i = NULL;
    double *x = NULL, *x_i = NULL;
    double *ferr = NULL, *ferr_i = NULL;
    double *berr = NULL, *berr_i = NULL;
    double *work = NULL, *work_i = NULL;
    lapack_int *iwork = NULL, *iwork_i = NULL;
    double *x_save = NULL;
    double *ferr_save = NULL;
    double *berr_save = NULL;
    double *ab_r = NULL;
    double *afb_r = NULL;
    double *b_r = NULL;
    double *x_r = NULL;

    /* Iniitialize the scalar parameters */
    init_scalars_dgbrfs( &trans, &n, &kl, &ku, &nrhs, &ldab, &ldafb, &ldb,
                         &ldx );
    ldab_r = n+2;
    ldafb_r = n+2;
    ldb_r = nrhs+2;
    ldx_r = nrhs+2;
    trans_i = trans;
    n_i = n;
    kl_i = kl;
    ku_i = ku;
    nrhs_i = nrhs;
    ldab_i = ldab;
    ldafb_i = ldafb;
    ldb_i = ldb;
    ldx_i = ldx;

    /* Allocate memory for the LAPACK routine arrays */
    ab = (double *)LAPACKE_malloc( ldab*n * sizeof(double) );
    afb = (double *)LAPACKE_malloc( ldafb*n * sizeof(double) );
    ipiv = (lapack_int *)LAPACKE_malloc( n * sizeof(lapack_int) );
    b = (double *)LAPACKE_malloc( ldb*nrhs * sizeof(double) );
    x = (double *)LAPACKE_malloc( ldx*nrhs * sizeof(double) );
    ferr = (double *)LAPACKE_malloc( nrhs * sizeof(double) );
    berr = (double *)LAPACKE_malloc( nrhs * sizeof(double) );
    work = (double *)LAPACKE_malloc( 3*n * sizeof(double) );
    iwork = (lapack_int *)LAPACKE_malloc( n * sizeof(lapack_int) );

    /* Allocate memory for the C interface function arrays */
    ab_i = (double *)LAPACKE_malloc( ldab*n * sizeof(double) );
    afb_i = (double *)LAPACKE_malloc( ldafb*n * sizeof(double) );
    ipiv_i = (lapack_int *)LAPACKE_malloc( n * sizeof(lapack_int) );
    b_i = (double *)LAPACKE_malloc( ldb*nrhs * sizeof(double) );
    x_i = (double *)LAPACKE_malloc( ldx*nrhs * sizeof(double) );
    ferr_i = (double *)LAPACKE_malloc( nrhs * sizeof(double) );
    berr_i = (double *)LAPACKE_malloc( nrhs * sizeof(double) );
    work_i = (double *)LAPACKE_malloc( 3*n * sizeof(double) );
    iwork_i = (lapack_int *)LAPACKE_malloc( n * sizeof(lapack_int) );

    /* Allocate memory for the backup arrays */
    x_save = (double *)LAPACKE_malloc( ldx*nrhs * sizeof(double) );
    ferr_save = (double *)LAPACKE_malloc( nrhs * sizeof(double) );
    berr_save = (double *)LAPACKE_malloc( nrhs * sizeof(double) );

    /* Allocate memory for the row-major arrays */
    ab_r = (double *)LAPACKE_malloc( (kl+ku+1)*(n+2) * sizeof(double) );
    afb_r = (double *)LAPACKE_malloc( ((2*kl+ku+1)*(n+2)) * sizeof(double) );
    b_r = (double *)LAPACKE_malloc( n*(nrhs+2) * sizeof(double) );
    x_r = (double *)LAPACKE_malloc( n*(nrhs+2) * sizeof(double) );

    /* Initialize input arrays */
    init_ab( ldab*n, ab );
    init_afb( ldafb*n, afb );
    init_ipiv( n, ipiv );
    init_b( ldb*nrhs, b );
    init_x( ldx*nrhs, x );
    init_ferr( nrhs, ferr );
    init_berr( nrhs, berr );
    init_work( 3*n, work );
    init_iwork( n, iwork );

    /* Backup the ouptut arrays */
    for( i = 0; i < ldx*nrhs; i++ ) {
        x_save[i] = x[i];
    }
    for( i = 0; i < nrhs; i++ ) {
        ferr_save[i] = ferr[i];
    }
    for( i = 0; i < nrhs; i++ ) {
        berr_save[i] = berr[i];
    }

    /* Call the LAPACK routine */
    dgbrfs_( &trans, &n, &kl, &ku, &nrhs, ab, &ldab, afb, &ldafb, ipiv, b, &ldb,
             x, &ldx, ferr, berr, work, iwork, &info );

    /* Initialize input data, call the column-major middle-level
     * interface to LAPACK routine and check the results */
    for( i = 0; i < ldab*n; i++ ) {
        ab_i[i] = ab[i];
    }
    for( i = 0; i < ldafb*n; i++ ) {
        afb_i[i] = afb[i];
    }
    for( i = 0; i < n; i++ ) {
        ipiv_i[i] = ipiv[i];
    }
    for( i = 0; i < ldb*nrhs; i++ ) {
        b_i[i] = b[i];
    }
    for( i = 0; i < ldx*nrhs; i++ ) {
        x_i[i] = x_save[i];
    }
    for( i = 0; i < nrhs; i++ ) {
        ferr_i[i] = ferr_save[i];
    }
    for( i = 0; i < nrhs; i++ ) {
        berr_i[i] = berr_save[i];
    }
    for( i = 0; i < 3*n; i++ ) {
        work_i[i] = work[i];
    }
    for( i = 0; i < n; i++ ) {
        iwork_i[i] = iwork[i];
    }
    info_i = LAPACKE_dgbrfs_work( LAPACK_COL_MAJOR, trans_i, n_i, kl_i, ku_i,
                                  nrhs_i, ab_i, ldab_i, afb_i, ldafb_i, ipiv_i,
                                  b_i, ldb_i, x_i, ldx_i, ferr_i, berr_i,
                                  work_i, iwork_i );

    failed = compare_dgbrfs( x, x_i, ferr, ferr_i, berr, berr_i, info, info_i,
                             ldx, nrhs );
    if( failed == 0 ) {
        printf( "PASSED: column-major middle-level interface to dgbrfs\n" );
    } else {
        printf( "FAILED: column-major middle-level interface to dgbrfs\n" );
    }

    /* Initialize input data, call the column-major high-level
     * interface to LAPACK routine and check the results */
    for( i = 0; i < ldab*n; i++ ) {
        ab_i[i] = ab[i];
    }
    for( i = 0; i < ldafb*n; i++ ) {
        afb_i[i] = afb[i];
    }
    for( i = 0; i < n; i++ ) {
        ipiv_i[i] = ipiv[i];
    }
    for( i = 0; i < ldb*nrhs; i++ ) {
        b_i[i] = b[i];
    }
    for( i = 0; i < ldx*nrhs; i++ ) {
        x_i[i] = x_save[i];
    }
    for( i = 0; i < nrhs; i++ ) {
        ferr_i[i] = ferr_save[i];
    }
    for( i = 0; i < nrhs; i++ ) {
        berr_i[i] = berr_save[i];
    }
    for( i = 0; i < 3*n; i++ ) {
        work_i[i] = work[i];
    }
    for( i = 0; i < n; i++ ) {
        iwork_i[i] = iwork[i];
    }
    info_i = LAPACKE_dgbrfs( LAPACK_COL_MAJOR, trans_i, n_i, kl_i, ku_i, nrhs_i,
                             ab_i, ldab_i, afb_i, ldafb_i, ipiv_i, b_i, ldb_i,
                             x_i, ldx_i, ferr_i, berr_i );

    failed = compare_dgbrfs( x, x_i, ferr, ferr_i, berr, berr_i, info, info_i,
                             ldx, nrhs );
    if( failed == 0 ) {
        printf( "PASSED: column-major high-level interface to dgbrfs\n" );
    } else {
        printf( "FAILED: column-major high-level interface to dgbrfs\n" );
    }

    /* Initialize input data, call the row-major middle-level
     * interface to LAPACK routine and check the results */
    for( i = 0; i < ldab*n; i++ ) {
        ab_i[i] = ab[i];
    }
    for( i = 0; i < ldafb*n; i++ ) {
        afb_i[i] = afb[i];
    }
    for( i = 0; i < n; i++ ) {
        ipiv_i[i] = ipiv[i];
    }
    for( i = 0; i < ldb*nrhs; i++ ) {
        b_i[i] = b[i];
    }
    for( i = 0; i < ldx*nrhs; i++ ) {
        x_i[i] = x_save[i];
    }
    for( i = 0; i < nrhs; i++ ) {
        ferr_i[i] = ferr_save[i];
    }
    for( i = 0; i < nrhs; i++ ) {
        berr_i[i] = berr_save[i];
    }
    for( i = 0; i < 3*n; i++ ) {
        work_i[i] = work[i];
    }
    for( i = 0; i < n; i++ ) {
        iwork_i[i] = iwork[i];
    }

    LAPACKE_dge_trans( LAPACK_COL_MAJOR, kl+ku+1, n, ab_i, ldab, ab_r, n+2 );
    LAPACKE_dge_trans( LAPACK_COL_MAJOR, 2*kl+ku+1, n, afb_i, ldafb, afb_r,
                       n+2 );
    LAPACKE_dge_trans( LAPACK_COL_MAJOR, n, nrhs, b_i, ldb, b_r, nrhs+2 );
    LAPACKE_dge_trans( LAPACK_COL_MAJOR, n, nrhs, x_i, ldx, x_r, nrhs+2 );
    info_i = LAPACKE_dgbrfs_work( LAPACK_ROW_MAJOR, trans_i, n_i, kl_i, ku_i,
                                  nrhs_i, ab_r, ldab_r, afb_r, ldafb_r, ipiv_i,
                                  b_r, ldb_r, x_r, ldx_r, ferr_i, berr_i,
                                  work_i, iwork_i );

    LAPACKE_dge_trans( LAPACK_ROW_MAJOR, n, nrhs, x_r, nrhs+2, x_i, ldx );

    failed = compare_dgbrfs( x, x_i, ferr, ferr_i, berr, berr_i, info, info_i,
                             ldx, nrhs );
    if( failed == 0 ) {
        printf( "PASSED: row-major middle-level interface to dgbrfs\n" );
    } else {
        printf( "FAILED: row-major middle-level interface to dgbrfs\n" );
    }

    /* Initialize input data, call the row-major high-level
     * interface to LAPACK routine and check the results */
    for( i = 0; i < ldab*n; i++ ) {
        ab_i[i] = ab[i];
    }
    for( i = 0; i < ldafb*n; i++ ) {
        afb_i[i] = afb[i];
    }
    for( i = 0; i < n; i++ ) {
        ipiv_i[i] = ipiv[i];
    }
    for( i = 0; i < ldb*nrhs; i++ ) {
        b_i[i] = b[i];
    }
    for( i = 0; i < ldx*nrhs; i++ ) {
        x_i[i] = x_save[i];
    }
    for( i = 0; i < nrhs; i++ ) {
        ferr_i[i] = ferr_save[i];
    }
    for( i = 0; i < nrhs; i++ ) {
        berr_i[i] = berr_save[i];
    }
    for( i = 0; i < 3*n; i++ ) {
        work_i[i] = work[i];
    }
    for( i = 0; i < n; i++ ) {
        iwork_i[i] = iwork[i];
    }

    /* Init row_major arrays */
    LAPACKE_dge_trans( LAPACK_COL_MAJOR, kl+ku+1, n, ab_i, ldab, ab_r, n+2 );
    LAPACKE_dge_trans( LAPACK_COL_MAJOR, 2*kl+ku+1, n, afb_i, ldafb, afb_r,
                       n+2 );
    LAPACKE_dge_trans( LAPACK_COL_MAJOR, n, nrhs, b_i, ldb, b_r, nrhs+2 );
    LAPACKE_dge_trans( LAPACK_COL_MAJOR, n, nrhs, x_i, ldx, x_r, nrhs+2 );
    info_i = LAPACKE_dgbrfs( LAPACK_ROW_MAJOR, trans_i, n_i, kl_i, ku_i, nrhs_i,
                             ab_r, ldab_r, afb_r, ldafb_r, ipiv_i, b_r, ldb_r,
                             x_r, ldx_r, ferr_i, berr_i );

    LAPACKE_dge_trans( LAPACK_ROW_MAJOR, n, nrhs, x_r, nrhs+2, x_i, ldx );

    failed = compare_dgbrfs( x, x_i, ferr, ferr_i, berr, berr_i, info, info_i,
                             ldx, nrhs );
    if( failed == 0 ) {
        printf( "PASSED: row-major high-level interface to dgbrfs\n" );
    } else {
        printf( "FAILED: row-major high-level interface to dgbrfs\n" );
    }

    /* Release memory */
    if( ab != NULL ) {
        LAPACKE_free( ab );
    }
    if( ab_i != NULL ) {
        LAPACKE_free( ab_i );
    }
    if( ab_r != NULL ) {
        LAPACKE_free( ab_r );
    }
    if( afb != NULL ) {
        LAPACKE_free( afb );
    }
    if( afb_i != NULL ) {
        LAPACKE_free( afb_i );
    }
    if( afb_r != NULL ) {
        LAPACKE_free( afb_r );
    }
    if( ipiv != NULL ) {
        LAPACKE_free( ipiv );
    }
    if( ipiv_i != NULL ) {
        LAPACKE_free( ipiv_i );
    }
    if( b != NULL ) {
        LAPACKE_free( b );
    }
    if( b_i != NULL ) {
        LAPACKE_free( b_i );
    }
    if( b_r != NULL ) {
        LAPACKE_free( b_r );
    }
    if( x != NULL ) {
        LAPACKE_free( x );
    }
    if( x_i != NULL ) {
        LAPACKE_free( x_i );
    }
    if( x_r != NULL ) {
        LAPACKE_free( x_r );
    }
    if( x_save != NULL ) {
        LAPACKE_free( x_save );
    }
    if( ferr != NULL ) {
        LAPACKE_free( ferr );
    }
    if( ferr_i != NULL ) {
        LAPACKE_free( ferr_i );
    }
    if( ferr_save != NULL ) {
        LAPACKE_free( ferr_save );
    }
    if( berr != NULL ) {
        LAPACKE_free( berr );
    }
    if( berr_i != NULL ) {
        LAPACKE_free( berr_i );
    }
    if( berr_save != NULL ) {
        LAPACKE_free( berr_save );
    }
    if( work != NULL ) {
        LAPACKE_free( work );
    }
    if( work_i != NULL ) {
        LAPACKE_free( work_i );
    }
    if( iwork != NULL ) {
        LAPACKE_free( iwork );
    }
    if( iwork_i != NULL ) {
        LAPACKE_free( iwork_i );
    }

    return 0;
}

/* Auxiliary function: dgbrfs scalar parameters initialization */
static void init_scalars_dgbrfs( char *trans, lapack_int *n, lapack_int *kl,
                                 lapack_int *ku, lapack_int *nrhs,
                                 lapack_int *ldab, lapack_int *ldafb,
                                 lapack_int *ldb, lapack_int *ldx )
{
    *trans = 'N';
    *n = 4;
    *kl = 1;
    *ku = 2;
    *nrhs = 2;
    *ldab = 17;
    *ldafb = 25;
    *ldb = 8;
    *ldx = 8;

    return;
}

/* Auxiliary functions: dgbrfs array parameters initialization */
static void init_ab( lapack_int size, double *ab ) {
    lapack_int i;
    for( i = 0; i < size; i++ ) {
        ab[i] = 0;
    }
    ab[0] = 0.00000000000000000e+000;  /* ab[0,0] */
    ab[17] = 0.00000000000000000e+000;  /* ab[0,1] */
    ab[34] = -3.66000000000000010e+000;  /* ab[0,2] */
    ab[51] = -2.12999999999999990e+000;  /* ab[0,3] */
    ab[1] = 0.00000000000000000e+000;  /* ab[1,0] */
    ab[18] = 2.54000000000000000e+000;  /* ab[1,1] */
    ab[35] = -2.73000000000000000e+000;  /* ab[1,2] */
    ab[52] = 4.07000000000000030e+000;  /* ab[1,3] */
    ab[2] = -2.30000000000000010e-001;  /* ab[2,0] */
    ab[19] = 2.46000000000000000e+000;  /* ab[2,1] */
    ab[36] = 2.46000000000000000e+000;  /* ab[2,2] */
    ab[53] = -3.81999999999999980e+000;  /* ab[2,3] */
    ab[3] = -6.98000000000000040e+000;  /* ab[3,0] */
    ab[20] = 2.56000000000000010e+000;  /* ab[3,1] */
    ab[37] = -4.78000000000000020e+000;  /* ab[3,2] */
    ab[54] = 0.00000000000000000e+000;  /* ab[3,3] */
}
static void init_afb( lapack_int size, double *afb ) {
    lapack_int i;
    for( i = 0; i < size; i++ ) {
        afb[i] = 0;
    }
    afb[0] = 0.00000000000000000e+000;  /* afb[0,0] */
    afb[25] = 0.00000000000000000e+000;  /* afb[0,1] */
    afb[50] = 0.00000000000000000e+000;  /* afb[0,2] */
    afb[75] = -2.12999999999999990e+000;  /* afb[0,3] */
    afb[1] = 0.00000000000000000e+000;  /* afb[1,0] */
    afb[26] = 0.00000000000000000e+000;  /* afb[1,1] */
    afb[51] = -2.73000000000000000e+000;  /* afb[1,2] */
    afb[76] = 4.07000000000000030e+000;  /* afb[1,3] */
    afb[2] = 0.00000000000000000e+000;  /* afb[2,0] */
    afb[27] = 2.46000000000000000e+000;  /* afb[2,1] */
    afb[52] = 2.46000000000000000e+000;  /* afb[2,2] */
    afb[77] = -3.83914387088108940e+000;  /* afb[2,3] */
    afb[3] = -6.98000000000000040e+000;  /* afb[3,0] */
    afb[28] = 2.56000000000000010e+000;  /* afb[3,1] */
    afb[53] = -5.93293047098853950e+000;  /* afb[3,2] */
    afb[78] = -7.26906663992311850e-001;  /* afb[3,3] */
    afb[4] = 3.29512893982807990e-002;  /* afb[4,0] */
    afb[29] = 9.60523370343839610e-001;  /* afb[4,1] */
    afb[54] = 8.05672681211037410e-001;  /* afb[4,2] */
    afb[79] = 0.00000000000000000e+000;  /* afb[4,3] */
}
static void init_ipiv( lapack_int size, lapack_int *ipiv ) {
    lapack_int i;
    for( i = 0; i < size; i++ ) {
        ipiv[i] = 0;
    }
    ipiv[0] = 2;
    ipiv[1] = 3;
    ipiv[2] = 3;
    ipiv[3] = 4;
}
static void init_b( lapack_int size, double *b ) {
    lapack_int i;
    for( i = 0; i < size; i++ ) {
        b[i] = 0;
    }
    b[0] = 4.41999999999999990e+000;  /* b[0,0] */
    b[8] = -3.60099999999999980e+001;  /* b[0,1] */
    b[1] = 2.71299999999999990e+001;  /* b[1,0] */
    b[9] = -3.16700000000000020e+001;  /* b[1,1] */
    b[2] = -6.13999999999999970e+000;  /* b[2,0] */
    b[10] = -1.15999999999999990e+000;  /* b[2,1] */
    b[3] = 1.05000000000000000e+001;  /* b[3,0] */
    b[11] = -2.58200000000000000e+001;  /* b[3,1] */
}
static void init_x( lapack_int size, double *x ) {
    lapack_int i;
    for( i = 0; i < size; i++ ) {
        x[i] = 0;
    }
    x[0] = -2.00000000000000040e+000;  /* x[0,0] */
    x[8] = 9.99999999999998000e-001;  /* x[0,1] */
    x[1] = 3.00000000000000040e+000;  /* x[1,0] */
    x[9] = -4.00000000000000440e+000;  /* x[1,1] */
    x[2] = 1.00000000000000090e+000;  /* x[2,0] */
    x[10] = 6.99999999999999560e+000;  /* x[2,1] */
    x[3] = -4.00000000000000090e+000;  /* x[3,0] */
    x[11] = -1.99999999999999380e+000;  /* x[3,1] */
}
static void init_ferr( lapack_int size, double *ferr ) {
    lapack_int i;
    for( i = 0; i < size; i++ ) {
        ferr[i] = 0;
    }
}
static void init_berr( lapack_int size, double *berr ) {
    lapack_int i;
    for( i = 0; i < size; i++ ) {
        berr[i] = 0;
    }
}
static void init_work( lapack_int size, double *work ) {
    lapack_int i;
    for( i = 0; i < size; i++ ) {
        work[i] = 0;
    }
}
static void init_iwork( lapack_int size, lapack_int *iwork ) {
    lapack_int i;
    for( i = 0; i < size; i++ ) {
        iwork[i] = 0;
    }
}

/* Auxiliary function: C interface to dgbrfs results check */
/* Return value: 0 - test is passed, non-zero - test is failed */
static int compare_dgbrfs( double *x, double *x_i, double *ferr, double *ferr_i,
                           double *berr, double *berr_i, lapack_int info,
                           lapack_int info_i, lapack_int ldx, lapack_int nrhs )
{
    lapack_int i;
    int failed = 0;
    for( i = 0; i < ldx*nrhs; i++ ) {
        failed += compare_doubles(x[i],x_i[i]);
    }
    for( i = 0; i < nrhs; i++ ) {
        failed += compare_doubles(ferr[i],ferr_i[i]);
    }
    for( i = 0; i < nrhs; i++ ) {
        failed += compare_doubles(berr[i],berr_i[i]);
    }
    failed += (info == info_i) ? 0 : 1;
    if( info != 0 || info_i != 0 ) {
        printf( "info=%d, info_i=%d\n",(int)info,(int)info_i );
    }

    return failed;
}