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*****************************************************************************
* Contents: Native high-level C interface to LAPACK function dbdsvdx
* Author: Intel Corporation
*****************************************************************************/

#include "lapacke_utils.h"

lapack_int LAPACKE_dbdsvdx( int matrix_layout, char uplo, char jobz, char range,
                           lapack_int n, double* d, double* e,
                           double vl, double vu,
                           lapack_int il, lapack_int iu, lapack_int* ns,
                           double* s, double* z, lapack_int ldz,
                           lapack_int* superb )
{
    lapack_int info = 0;
    lapack_int lwork = MAX(14*n,1);
    double* work = NULL;
    lapack_int* iwork = NULL;
    lapack_int i;
    if( matrix_layout != LAPACK_COL_MAJOR && matrix_layout != LAPACK_ROW_MAJOR ) {
        LAPACKE_xerbla( "LAPACKE_dbdsvdx", -1 );
        return -1;
    }
#ifndef LAPACK_DISABLE_NAN_CHECK
    if( LAPACKE_get_nancheck() ) {
        /* Optionally check input matrices for NaNs */
        if( LAPACKE_d_nancheck( n, d, 1 ) ) {
            return -6;
        }
        if( LAPACKE_d_nancheck( n - 1, e, 1 ) ) {
            return -7;
        }
    }
#endif
    /* Allocate memory for work arrays */
    work = (double*)LAPACKE_malloc( sizeof(double) * lwork );
    if( work == NULL ) {
        info = LAPACK_WORK_MEMORY_ERROR;
        goto exit_level_0;
    }
    iwork = (lapack_int*)LAPACKE_malloc( sizeof(lapack_int) * MAX(12*n,1) );
    if( iwork == NULL ) {
        info = LAPACK_WORK_MEMORY_ERROR;
        goto exit_level_1;
    }
    /* Call middle-level interface */
    info = LAPACKE_dbdsvdx_work( matrix_layout, uplo, jobz,  range,
                                 n, d, e, vl, vu, il, iu, ns, s, z,
                                 ldz, work, iwork);
    /* Backup significant data from working array(s) */
    for( i=0; i<12*n-1; i++ ) {
        superb[i] = iwork[i+1];
    }
    /* Release memory and exit */
    LAPACKE_free( iwork );
exit_level_1:
    LAPACKE_free( work );
exit_level_0:
    if( info == LAPACK_WORK_MEMORY_ERROR ) {
        LAPACKE_xerbla( "LAPACKE_dbdsvdx", info );
    }
    return info;
}
