Example #1
0
/**
    Purpose
    -------
    DLAEX3 finds the roots of the secular equation, as defined by the
    values in D, W, and RHO, between 1 and K.  It makes the
    appropriate calls to DLAED4 and then updates the eigenvectors by
    multiplying the matrix of eigenvectors of the pair of eigensystems
    being combined by the matrix of eigenvectors of the K-by-K system
    which is solved here.

    It is used in the last step when only a part of the eigenvectors
    is required.
    It compute only the required part of the eigenvectors and the rest
    is not used.

    This code makes very mild assumptions about floating point
    arithmetic. It will work on machines with a guard digit in
    add/subtract, or on those binary machines without guard digits
    which subtract like the Cray X-MP, Cray Y-MP, Cray C-90, or Cray-2.
    It could conceivably fail on hexadecimal or decimal machines
    without guard digits, but we know of none.

    Arguments
    ---------
    @param[in]
    k       INTEGER
            The number of terms in the rational function to be solved by
            DLAED4.  K >= 0.

    @param[in]
    n       INTEGER
            The number of rows and columns in the Q matrix.
            N >= K (deflation may result in N > K).

    @param[in]
    n1      INTEGER
            The location of the last eigenvalue in the leading submatrix.
            min(1,N) <= N1 <= N/2.

    @param[out]
    d       DOUBLE PRECISION array, dimension (N)
            D(I) contains the updated eigenvalues for
            1 <= I <= K.

    @param[out]
    Q       DOUBLE PRECISION array, dimension (LDQ,N)
            Initially the first K columns are used as workspace.
            On output the columns ??? to ??? contain
            the updated eigenvectors.

    @param[in]
    ldq     INTEGER
            The leading dimension of the array Q.  LDQ >= max(1,N).

    @param[in]
    rho     DOUBLE PRECISION
            The value of the parameter in the rank one update equation.
            RHO >= 0 required.

    @param[in,out]
    dlamda  DOUBLE PRECISION array, dimension (K)
            The first K elements of this array contain the old roots
            of the deflated updating problem.  These are the poles
            of the secular equation. May be changed on output by
            having lowest order bit set to zero on Cray X-MP, Cray Y-MP,
            Cray-2, or Cray C-90, as described above.

    @param[in]
    Q2      DOUBLE PRECISION array, dimension (LDQ2, N)
            The first K columns of this matrix contain the non-deflated
            eigenvectors for the split problem.
            TODO what is LDQ2?

    @param[in]
    indx    INTEGER array, dimension (N)
            The permutation used to arrange the columns of the deflated
            Q matrix into three groups (see DLAED2).
            The rows of the eigenvectors found by DLAED4 must be likewise
            permuted before the matrix multiply can take place.

    @param[in]
    ctot    INTEGER array, dimension (4)
            A count of the total number of the various types of columns
            in Q, as described in INDX.  The fourth column type is any
            column which has been deflated.

    @param[in,out]
    w       DOUBLE PRECISION array, dimension (K)
            The first K elements of this array contain the components
            of the deflation-adjusted updating vector. Destroyed on
            output.

    @param
    s       (workspace) DOUBLE PRECISION array, dimension (N1 + 1)*K
            Will contain the eigenvectors of the repaired matrix which
            will be multiplied by the previously accumulated eigenvectors
            to update the system.

    @param[out]
    indxq   INTEGER array, dimension (N)
            On exit, the permutation which will reintegrate the
            subproblems back into sorted order,
            i.e. D( INDXQ( I = 1, N ) ) will be in ascending order.

    @param
    dwork   (workspace) DOUBLE PRECISION array, dimension (3*N*N/2+3*N)

    @param[in]
    range   magma_range_t
      -     = MagmaRangeAll: all eigenvalues will be found.
      -     = MagmaRangeV:   all eigenvalues in the half-open interval (VL,VU]
                             will be found.
      -     = MagmaRangeI:   the IL-th through IU-th eigenvalues will be found.
            TODO verify range, vl, vu, il, iu -- copied from dlaex1.

    @param[in]
    vl      DOUBLE PRECISION
    @param[in]
    vu      DOUBLE PRECISION
            if RANGE=MagmaRangeV, the lower and upper bounds of the interval to
            be searched for eigenvalues. VL < VU.
            Not referenced if RANGE = MagmaRangeAll or MagmaRangeI.

    @param[in]
    il      INTEGER
    @param[in]
    iu      INTEGER
            if RANGE=MagmaRangeI, the indices (in ascending order) of the
            smallest and largest eigenvalues to be returned.
            1 <= IL <= IU <= N, if N > 0; IL = 1 and IU = 0 if N = 0.
            Not referenced if RANGE = MagmaRangeAll or MagmaRangeV.

    @param[out]
    info    INTEGER
      -     = 0:  successful exit.
      -     < 0:  if INFO = -i, the i-th argument had an illegal value.
      -     > 0:  if INFO = 1, an eigenvalue did not converge

    Further Details
    ---------------
    Based on contributions by
    Jeff Rutter, Computer Science Division, University of California
    at Berkeley, USA
    Modified by Francoise Tisseur, University of Tennessee.

    @ingroup magma_dsyev_aux
    ********************************************************************/
extern "C" magma_int_t
magma_dlaex3(magma_int_t k, magma_int_t n, magma_int_t n1, double* d,
             double* Q, magma_int_t ldq, double rho,
             double* dlamda, double* Q2, magma_int_t* indx,
             magma_int_t* ctot, double* w, double* s, magma_int_t* indxq,
             double* dwork,
             magma_range_t range, double vl, double vu, magma_int_t il, magma_int_t iu,
             magma_int_t* info )
{
#define Q(i_,j_) (Q + (i_) + (j_)*ldq)

    double d_one  = 1.;
    double d_zero = 0.;
    magma_int_t ione = 1;
    magma_int_t ineg_one = -1;

    magma_int_t iil, iiu, rk;

    double* dq2= dwork;
    double* ds = dq2  + n*(n/2+1);
    double* dq = ds   + n*(n/2+1);
    magma_int_t lddq = n/2 + 1;

    magma_int_t i, iq2, j, n12, n2, n23, tmp, lq2;
    double temp;
    magma_int_t alleig, valeig, indeig;

    alleig = (range == MagmaRangeAll);
    valeig = (range == MagmaRangeV);
    indeig = (range == MagmaRangeI);

    *info = 0;

    if (k < 0)
        *info=-1;
    else if (n < k)
        *info=-2;
    else if (ldq < max(1,n))
        *info=-6;
    else if (! (alleig || valeig || indeig))
        *info = -15;
    else {
        if (valeig) {
            if (n > 0 && vu <= vl)
                *info = -17;
        }
        else if (indeig) {
            if (il < 1 || il > max(1,n))
                *info = -18;
            else if (iu < min(n,il) || iu > n)
                *info = -19;
        }
    }


    if (*info != 0) {
        magma_xerbla(__func__, -(*info));
        return *info;
    }

    // Quick return if possible
    if (k == 0)
        return *info;
    /*
     Modify values DLAMDA(i) to make sure all DLAMDA(i)-DLAMDA(j) can
     be computed with high relative accuracy (barring over/underflow).
     This is a problem on machines without a guard digit in
     add/subtract (Cray XMP, Cray YMP, Cray C 90 and Cray 2).
     The following code replaces DLAMDA(I) by 2*DLAMDA(I)-DLAMDA(I),
     which on any of these machines zeros out the bottommost
     bit of DLAMDA(I) if it is 1; this makes the subsequent
     subtractions DLAMDA(I)-DLAMDA(J) unproblematic when cancellation
     occurs. On binary machines with a guard digit (almost all
     machines) it does not change DLAMDA(I) at all. On hexadecimal
     and decimal machines with a guard digit, it slightly
     changes the bottommost bits of DLAMDA(I). It does not account
     for hexadecimal or decimal machines without guard digits
     (we know of none). We use a subroutine call to compute
     2*DLAMBDA(I) to prevent optimizing compilers from eliminating
     this code.*/

    n2 = n - n1;

    n12 = ctot[0] + ctot[1];
    n23 = ctot[1] + ctot[2];

    iq2 = n1 * n12;
    lq2 = iq2 + n2 * n23;

    magma_dsetvector_async( lq2, Q2, 1, dq2, 1, NULL );

#ifdef _OPENMP
    /////////////////////////////////////////////////////////////////////////////////
    //openmp implementation
    /////////////////////////////////////////////////////////////////////////////////
    magma_timer_t time=0;
    timer_start( time );

#pragma omp parallel private(i, j, tmp, temp)
    {
        magma_int_t id = omp_get_thread_num();
        magma_int_t tot = omp_get_num_threads();

        magma_int_t ib = (  id   * k) / tot; //start index of local loop
        magma_int_t ie = ((id+1) * k) / tot; //end index of local loop
        magma_int_t ik = ie - ib;           //number of local indices

        for (i = ib; i < ie; ++i)
            dlamda[i]=lapackf77_dlamc3(&dlamda[i], &dlamda[i]) - dlamda[i];

        for (j = ib; j < ie; ++j) {
            magma_int_t tmpp=j+1;
            magma_int_t iinfo = 0;
            lapackf77_dlaed4(&k, &tmpp, dlamda, w, Q(0,j), &rho, &d[j], &iinfo);
            // If the zero finder fails, the computation is terminated.
            if (iinfo != 0) {
#pragma omp critical (info)
                *info=iinfo;
                break;
            }
        }

#pragma omp barrier

        if (*info == 0) {
#pragma omp single
            {
                //Prepare the INDXQ sorting permutation.
                magma_int_t nk = n - k;
                lapackf77_dlamrg( &k, &nk, d, &ione, &ineg_one, indxq);

                //compute the lower and upper bound of the non-deflated eigenvectors
                if (valeig)
                    magma_dvrange(k, d, &iil, &iiu, vl, vu);
                else if (indeig)
                    magma_dirange(k, indxq, &iil, &iiu, il, iu);
                else {
                    iil = 1;
                    iiu = k;
                }
                rk = iiu - iil + 1;
            }

            if (k == 2) {
#pragma omp single
                {
                    for (j = 0; j < k; ++j) {
                        w[0] = *Q(0,j);
                        w[1] = *Q(1,j);

                        i = indx[0] - 1;
                        *Q(0,j) = w[i];
                        i = indx[1] - 1;
                        *Q(1,j) = w[i];
                    }
                }
            }
            else if (k != 1) {
                // Compute updated W.
                blasf77_dcopy( &ik, &w[ib], &ione, &s[ib], &ione);

                // Initialize W(I) = Q(I,I)
                tmp = ldq + 1;
                blasf77_dcopy( &ik, Q(ib,ib), &tmp, &w[ib], &ione);

                for (j = 0; j < k; ++j) {
                    magma_int_t i_tmp = min(j, ie);
                    for (i = ib; i < i_tmp; ++i)
                        w[i] = w[i] * ( *Q(i, j) / ( dlamda[i] - dlamda[j] ) );
                    i_tmp = max(j+1, ib);
                    for (i = i_tmp; i < ie; ++i)
                        w[i] = w[i] * ( *Q(i, j) / ( dlamda[i] - dlamda[j] ) );
                }

                for (i = ib; i < ie; ++i)
                    w[i] = copysign( sqrt( -w[i] ), s[i]);

#pragma omp barrier

                //reduce the number of used threads to have enough S workspace
                tot = min(n1, omp_get_num_threads());

                if (id < tot) {
                    ib = (  id   * rk) / tot + iil - 1;
                    ie = ((id+1) * rk) / tot + iil - 1;
                    ik = ie - ib;
                }
                else {
                    ib = -1;
                    ie = -1;
                    ik = -1;
                }

                // Compute eigenvectors of the modified rank-1 modification.
                for (j = ib; j < ie; ++j) {
                    for (i = 0; i < k; ++i)
                        s[id*k + i] = w[i] / *Q(i,j);
                    temp = magma_cblas_dnrm2( k, s+id*k, 1 );
                    for (i = 0; i < k; ++i) {
                        magma_int_t iii = indx[i] - 1;
                        *Q(i,j) = s[id*k + iii] / temp;
                    }
                }
            }
        }
    }
    if (*info != 0)
        return *info;

    timer_stop( time );
    timer_printf( "eigenvalues/vector D+zzT = %6.2f\n", time );

#else
    /////////////////////////////////////////////////////////////////////////////////
    // Non openmp implementation
    /////////////////////////////////////////////////////////////////////////////////
    magma_timer_t time=0;
    timer_start( time );

    for (i = 0; i < k; ++i)
        dlamda[i]=lapackf77_dlamc3(&dlamda[i], &dlamda[i]) - dlamda[i];

    for (j = 0; j < k; ++j) {
        magma_int_t tmpp=j+1;
        magma_int_t iinfo = 0;
        lapackf77_dlaed4(&k, &tmpp, dlamda, w, Q(0,j), &rho, &d[j], &iinfo);
        // If the zero finder fails, the computation is terminated.
        if (iinfo != 0)
            *info=iinfo;
    }
    if (*info != 0)
        return *info;

    //Prepare the INDXQ sorting permutation.
    magma_int_t nk = n - k;
    lapackf77_dlamrg( &k, &nk, d, &ione, &ineg_one, indxq);

    //compute the lower and upper bound of the non-deflated eigenvectors
    if (valeig)
        magma_dvrange(k, d, &iil, &iiu, vl, vu);
    else if (indeig)
        magma_dirange(k, indxq, &iil, &iiu, il, iu);
    else {
        iil = 1;
        iiu = k;
    }
    rk = iiu - iil + 1;

    if (k == 2) {
        for (j = 0; j < k; ++j) {
            w[0] = *Q(0,j);
            w[1] = *Q(1,j);

            i = indx[0] - 1;
            *Q(0,j) = w[i];
            i = indx[1] - 1;
            *Q(1,j) = w[i];
        }
    }
    else if (k != 1) {
        // Compute updated W.
        blasf77_dcopy( &k, w, &ione, s, &ione);

        // Initialize W(I) = Q(I,I)
        tmp = ldq + 1;
        blasf77_dcopy( &k, Q, &tmp, w, &ione);

        for (j = 0; j < k; ++j) {
            for (i = 0; i < j; ++i)
                w[i] = w[i] * ( *Q(i, j) / ( dlamda[i] - dlamda[j] ) );
            for (i = j+1; i < k; ++i)
                w[i] = w[i] * ( *Q(i, j) / ( dlamda[i] - dlamda[j] ) );
        }

        for (i = 0; i < k; ++i)
            w[i] = copysign( sqrt( -w[i] ), s[i]);

        // Compute eigenvectors of the modified rank-1 modification.
        for (j = iil-1; j < iiu; ++j) {
            for (i = 0; i < k; ++i)
                s[i] = w[i] / *Q(i,j);
            temp = magma_cblas_dnrm2( k, s, 1 );
            for (i = 0; i < k; ++i) {
                magma_int_t iii = indx[i] - 1;
                *Q(i,j) = s[iii] / temp;
            }
        }
    }

    timer_stop( time );
    timer_printf( "eigenvalues/vector D+zzT = %6.2f\n", time );

#endif //_OPENMP
    // Compute the updated eigenvectors.

    timer_start( time );
    magma_queue_sync( NULL );

    if (rk != 0) {
        if ( n23 != 0 ) {
            if (rk < magma_get_dlaed3_k()) {
                lapackf77_dlacpy("A", &n23, &rk, Q(ctot[0],iil-1), &ldq, s, &n23);
                blasf77_dgemm("N", "N", &n2, &rk, &n23, &d_one, &Q2[iq2], &n2,
                              s, &n23, &d_zero, Q(n1,iil-1), &ldq );
            } else {
                magma_dsetmatrix( n23, rk, Q(ctot[0],iil-1), ldq, ds, n23 );
                magma_dgemm( MagmaNoTrans, MagmaNoTrans, n2, rk, n23, d_one, &dq2[iq2], n2, ds, n23, d_zero, dq, lddq);
                magma_dgetmatrix( n2, rk, dq, lddq, Q(n1,iil-1), ldq );
            }
        } else
            lapackf77_dlaset("A", &n2, &rk, &d_zero, &d_zero, Q(n1,iil-1), &ldq);

        if ( n12 != 0 ) {
            if (rk < magma_get_dlaed3_k()) {
                lapackf77_dlacpy("A", &n12, &rk, Q(0,iil-1), &ldq, s, &n12);
                blasf77_dgemm("N", "N", &n1, &rk, &n12, &d_one, Q2, &n1,
                              s, &n12, &d_zero, Q(0,iil-1), &ldq);
            } else {
                magma_dsetmatrix( n12, rk, Q(0,iil-1), ldq, ds, n12 );
                magma_dgemm( MagmaNoTrans, MagmaNoTrans, n1, rk, n12, d_one, dq2, n1, ds, n12, d_zero, dq, lddq);
                magma_dgetmatrix( n1, rk, dq, lddq, Q(0,iil-1), ldq );
            }
        } else
            lapackf77_dlaset("A", &n1, &rk, &d_zero, &d_zero, Q(0,iil-1), &ldq);
    }
    timer_stop( time );
    timer_printf( "gemms = %6.2f\n", time );

    return *info;
} /* magma_dlaex3 */
Example #2
0
extern "C" magma_int_t
magma_dgeev(
    magma_vec_t jobvl, magma_vec_t jobvr, magma_int_t n,
    double *a, magma_int_t lda,
    double *WR, double *WI,
    double *vl, magma_int_t ldvl,
    double *vr, magma_int_t ldvr,
    double *work, magma_int_t lwork,
    magma_queue_t queue,
    magma_int_t *info)
{
/*  -- clMAGMA (version 1.3.0) --
       Univ. of Tennessee, Knoxville
       Univ. of California, Berkeley
       Univ. of Colorado, Denver
       @date November 2014

    Purpose
    =======
    DGEEV computes for an N-by-N real nonsymmetric matrix A, the
    eigenvalues and, optionally, the left and/or right eigenvectors.

    The right eigenvector v(j) of A satisfies
                     A * v(j) = lambda(j) * v(j)
    where lambda(j) is its eigenvalue.
    The left eigenvector u(j) of A satisfies
                  u(j)**T * A = lambda(j) * u(j)**T
    where u(j)**T denotes the transpose of u(j).

    The computed eigenvectors are normalized to have Euclidean norm
    equal to 1 and largest component real.

    Arguments
    =========
    JOBVL   (input) CHARACTER*1
            = 'N': left eigenvectors of A are not computed;
            = 'V': left eigenvectors of are computed.

    JOBVR   (input) CHARACTER*1
            = 'N': right eigenvectors of A are not computed;
            = 'V': right eigenvectors of A are computed.

    N       (input) INTEGER
            The order of the matrix A. N >= 0.

    A       (input/output) DOUBLE PRECISION array, dimension (LDA,N)
            On entry, the N-by-N matrix A.
            On exit, A has been overwritten.

    LDA     (input) INTEGER
            The leading dimension of the array A.  LDA >= max(1,N).

    WR      (output) DOUBLE PRECISION array, dimension (N)
    WI      (output) DOUBLE PRECISION array, dimension (N)
            WR and WI contain the real and imaginary parts,
            respectively, of the computed eigenvalues.  Complex
            conjugate pairs of eigenvalues appear consecutively
            with the eigenvalue having the positive imaginary part
            first.

    VL      (output) DOUBLE PRECISION array, dimension (LDVL,N)
            If JOBVL = 'V', the left eigenvectors u(j) are stored one
            after another in the columns of VL, in the same order
            as their eigenvalues.
            If JOBVL = 'N', VL is not referenced.
            u(j) = VL(:,j), the j-th column of VL.

    LDVL    (input) INTEGER
            The leading dimension of the array VL.  LDVL >= 1; if
            JOBVL = 'V', LDVL >= N.

    VR      (output) DOUBLE PRECISION array, dimension (LDVR,N)
            If JOBVR = 'V', the right eigenvectors v(j) are stored one
            after another in the columns of VR, in the same order
            as their eigenvalues.
            If JOBVR = 'N', VR is not referenced.
            v(j) = VR(:,j), the j-th column of VR.

    LDVR    (input) INTEGER
            The leading dimension of the array VR.  LDVR >= 1; if
            JOBVR = 'V', LDVR >= N.

    WORK    (workspace/output) DOUBLE PRECISION array, dimension (MAX(1,LWORK))
            On exit, if INFO = 0, WORK(1) returns the optimal LWORK.

    LWORK   (input) INTEGER
            The dimension of the array WORK.  LWORK >= (1+nb)*N.

            If LWORK = -1, then a workspace query is assumed; the routine
            only calculates the optimal size of the WORK array, returns
            this value as the first entry of the WORK array, and no error
            message related to LWORK is issued by XERBLA.

    INFO    (output) INTEGER
            = 0:  successful exit
            < 0:  if INFO = -i, the i-th argument had an illegal value.
            > 0:  if INFO = i, the QR algorithm failed to compute all the
                  eigenvalues, and no eigenvectors have been computed;
                  elements and i+1:N of W contain eigenvalues which have
                  converged.
    =====================================================================    */

    magma_int_t ione = 1;
    magma_int_t c__1 = 1;
    magma_int_t c__0 = 0;
    magma_int_t c_n1 = -1;
    
    magma_int_t a_dim1, a_offset, vl_dim1, vl_offset, vr_dim1, vr_offset, i__1,
            i__2, i__3;
    double d__1, d__2;

    magma_int_t i__, k, ihi, ilo;
    double      r__, cs, sn, scl;
    double dum[1], eps;
    magma_int_t ibal;
    double anrm;
    magma_int_t ierr, itau, iwrk, nout;
    magma_int_t scalea;
    double cscale;
    double bignum;
    magma_int_t minwrk;
    magma_int_t wantvl;
    double smlnum;
    magma_int_t lquery, wantvr, select[1];

    magma_int_t nb = 0;
    magmaDouble_ptr dT;
    //magma_timestr_t start, end;

    const char* side_ = NULL;

    *info = 0;
    lquery = lwork == -1;
    wantvl = (jobvl == MagmaVec);
    wantvr = (jobvr == MagmaVec);
    if (! wantvl && jobvl != MagmaNoVec) {
        *info = -1;
    } else if (! wantvr && jobvr != MagmaNoVec) {
        *info = -2;
    } else if (n < 0) {
        *info = -3;
    } else if (lda < max(1,n)) {
        *info = -5;
    } else if ( (ldvl < 1) || (wantvl && (ldvl < n))) {
        *info = -9;
    } else if ( (ldvr < 1) || (wantvr && (ldvr < n))) {
        *info = -11;
    }

    /*  Compute workspace   */
    if (*info == 0) {

        nb = magma_get_dgehrd_nb(n);
        minwrk = (2+nb)*n;
        work[0] = (double) minwrk;
        
        if (lwork < minwrk && ! lquery) {
            *info = -13;
        }

    }

    if (*info != 0) {
        magma_xerbla( __func__, -(*info) );
        return *info;
    }
    else if (lquery) {
        return *info;
    }

    /* Quick return if possible */
    if (n == 0) {
        return *info;
    }
   
    // if eigenvectors are needed
#if defined(VERSION3)
    if (MAGMA_SUCCESS != magma_dmalloc( &dT, nb*n )) {
        *info = MAGMA_ERR_DEVICE_ALLOC;
        return *info;
    }
#endif

    // subtract row and col for 1-based indexing
    a_dim1   = lda;
    a_offset = 1 + a_dim1;
    a       -= a_offset;
    vl_dim1   = ldvl;
    vl_offset = 1 + vl_dim1;
    vl       -= vl_offset;
    vr_dim1   = ldvr;
    vr_offset = 1 + vr_dim1;
    vr       -= vr_offset;
    --work;

    /* Get machine constants */
    eps    = lapackf77_dlamch("P");
    smlnum = lapackf77_dlamch("S");
    bignum = 1. / smlnum;
    lapackf77_dlabad(&smlnum, &bignum);
    smlnum = magma_dsqrt(smlnum) / eps;
    bignum = 1. / smlnum;

    /* Scale A if max element outside range [SMLNUM,BIGNUM] */
    anrm = lapackf77_dlange("M", &n, &n, &a[a_offset], &lda, dum);
    scalea = 0;
    if (anrm > 0. && anrm < smlnum) {
        scalea = 1;
        cscale = smlnum;
    } else if (anrm > bignum) {
        scalea = 1;
        cscale = bignum;
    }
    if (scalea) {
        lapackf77_dlascl("G", &c__0, &c__0, &anrm, &cscale, &n, &n,
                &a[a_offset], &lda, &ierr);
    }

    /* Balance the matrix
       (Workspace: need N) */
    ibal = 1;
    lapackf77_dgebal("B", &n, &a[a_offset], &lda, &ilo, &ihi, &work[ibal], &ierr);

    /* Reduce to upper Hessenberg form
       (Workspace: need 3*N, prefer 2*N+N*NB) */
    itau = ibal + n;
    iwrk = itau + n;
    i__1 = lwork - iwrk + 1;

    //start = get_current_time();
#if defined(VERSION1)
    /*
     * Version 1 - LAPACK
     */
    lapackf77_dgehrd(&n, &ilo, &ihi, &a[a_offset], &lda,
                     &work[itau], &work[iwrk], &i__1, &ierr);
#elif defined(VERSION2)
    /*
     *  Version 2 - LAPACK consistent HRD
     */
    magma_dgehrd2(n, ilo, ihi, &a[a_offset], lda,
                  &work[itau], &work[iwrk], &i__1, &ierr);
#elif defined(VERSION3)
    /*
     * Version 3 - LAPACK consistent MAGMA HRD + matrices T stored,
     */
    magma_dgehrd(n, ilo, ihi, &a[a_offset], lda,
                 &work[itau], &work[iwrk], i__1, dT, 0, queue, &ierr);
#endif
    //end = get_current_time();
    //printf("    Time for dgehrd = %5.2f sec\n", GetTimerValue(start,end)/1000.);

    if (wantvl) {
      /*        Want left eigenvectors
                Copy Householder vectors to VL */
        side_ = "Left";
        lapackf77_dlacpy(MagmaLowerStr, &n, &n,
                         &a[a_offset], &lda, &vl[vl_offset], &ldvl);

        /*
         * Generate orthogonal matrix in VL
         *   (Workspace: need 3*N-1, prefer 2*N+(N-1)*NB)
         */
        i__1 = lwork - iwrk + 1;

        //start = get_current_time();
#if defined(VERSION1) || defined(VERSION2)
        /*
         * Version 1 & 2 - LAPACK
         */
        lapackf77_dorghr(&n, &ilo, &ihi, &vl[vl_offset], &ldvl,
                         &work[itau], &work[iwrk], &i__1, &ierr);
#elif defined(VERSION3)
        /*
         * Version 3 - LAPACK consistent MAGMA HRD + matrices T stored
         */
        magma_dorghr(n, ilo, ihi, &vl[vl_offset], ldvl, &work[itau],
                     dT, 0, nb, queue, &ierr);
#endif
        //end = get_current_time();
        //printf("    Time for dorghr = %5.2f sec\n", GetTimerValue(start,end)/1000.);

        /*
         * Perform QR iteration, accumulating Schur vectors in VL
         *   (Workspace: need N+1, prefer N+HSWORK (see comments) )
         */
        iwrk = itau;
        i__1 = lwork - iwrk + 1;
        lapackf77_dhseqr("S", "V", &n, &ilo, &ihi, &a[a_offset], &lda, WR, WI,
                         &vl[vl_offset], &ldvl, &work[iwrk], &i__1, info);

        if (wantvr) {
          /* Want left and right eigenvectors
             Copy Schur vectors to VR */
            side_ = "Both";
            lapackf77_dlacpy("F", &n, &n, &vl[vl_offset], &ldvl, &vr[vr_offset], &ldvr);
        }

    } else if (wantvr) {
        /*  Want right eigenvectors
            Copy Householder vectors to VR */
        side_ = "Right";
        lapackf77_dlacpy("L", &n, &n, &a[a_offset], &lda, &vr[vr_offset], &ldvr);

        /*
         * Generate orthogonal matrix in VR
         *   (Workspace: need 3*N-1, prefer 2*N+(N-1)*NB)
         */
        i__1 = lwork - iwrk + 1;
        //start = get_current_time();
#if defined(VERSION1) || defined(VERSION2)
        /*
         * Version 1 & 2 - LAPACK
         */
        lapackf77_dorghr(&n, &ilo, &ihi, &vr[vr_offset], &ldvr,
                         &work[itau], &work[iwrk], &i__1, &ierr);
#elif defined(VERSION3)
        /*
         * Version 3 - LAPACK consistent MAGMA HRD + matrices T stored
         */
        magma_dorghr(n, ilo, ihi, &vr[vr_offset], ldvr,
                     &work[itau], dT, 0, nb, queue, &ierr);
#endif
        //end = get_current_time();
        //printf("    Time for dorghr = %5.2f sec\n", GetTimerValue(start,end)/1000.);

        /*
         * Perform QR iteration, accumulating Schur vectors in VR
         *   (Workspace: need N+1, prefer N+HSWORK (see comments) )
         */
        iwrk = itau;
        i__1 = lwork - iwrk + 1;
        lapackf77_dhseqr("S", "V", &n, &ilo, &ihi, &a[a_offset], &lda, WR, WI,
                &vr[vr_offset], &ldvr, &work[iwrk], &i__1, info);
    } else {
        /*
         * Compute eigenvalues only
         *   (Workspace: need N+1, prefer N+HSWORK (see comments) )
         */
        iwrk = itau;
        i__1 = lwork - iwrk + 1;
        lapackf77_dhseqr("E", "N", &n, &ilo, &ihi, &a[a_offset], &lda, WR, WI,
                &vr[vr_offset], &ldvr, &work[iwrk], &i__1, info);
    }

    /* If INFO > 0 from DHSEQR, then quit */
    if (*info > 0) {
        fprintf(stderr, "DHSEQR returned with info = %d\n", (int) *info);
        goto L50;
    }

    if (wantvl || wantvr) {
        /*
         * Compute left and/or right eigenvectors
         *   (Workspace: need 4*N)
         */
        lapackf77_dtrevc(side_, "B", select, &n, &a[a_offset], &lda, &vl[vl_offset], &ldvl,
                &vr[vr_offset], &ldvr, &n, &nout, &work[iwrk], &ierr);
    }

    if (wantvl) {
        /*
         * Undo balancing of left eigenvectors
         *   (Workspace: need N)
         */
        lapackf77_dgebak("B", "L", &n, &ilo, &ihi,
                         &work[ibal], &n, &vl[vl_offset], &ldvl, &ierr);

        /* Normalize left eigenvectors and make largest component real */
        for (i__ = 1; i__ <= n; ++i__) {
            if ( WI[i__-1] == 0.) {
                scl = magma_cblas_dnrm2(n, &vl[i__ * vl_dim1 + 1], 1);
                scl = 1. / scl;
                blasf77_dscal( &n, &scl, &vl[i__ * vl_dim1 + 1], &ione );
            } else if (WI[i__-1] > 0.) {
                d__1 = magma_cblas_dnrm2(n, &vl[ i__      * vl_dim1 + 1], 1);
                d__2 = magma_cblas_dnrm2(n, &vl[(i__ + 1) * vl_dim1 + 1], 1);
                scl = lapackf77_dlapy2(&d__1, &d__2);
                scl = 1. / scl;
                blasf77_dscal( &n, &scl, &vl[ i__      * vl_dim1 + 1], &ione );
                blasf77_dscal( &n, &scl, &vl[(i__ + 1) * vl_dim1 + 1], &ione );
                i__2 = n;
                for (k = 1; k <= i__2; ++k) {
                    /* Computing 2nd power */
                    d__1 = vl[k + i__ * vl_dim1];
                    /* Computing 2nd power */
                    d__2 = vl[k + (i__ + 1) * vl_dim1];
                    work[iwrk + k - 1] = d__1 * d__1 + d__2 * d__2;
                }
                /* Comment:
                   Fortran BLAS does not have to add 1
                   C       BLAS must add one to cblas_idamax */
                k = blasf77_idamax( &n, &work[iwrk], &ione );  //+1;
                lapackf77_dlartg(&vl[k +  i__      * vl_dim1],
                                 &vl[k + (i__ + 1) * vl_dim1], &cs, &sn, &r__);
                blasf77_drot( &n, &vl[ i__      * vl_dim1 + 1], &ione,
                                  &vl[(i__ + 1) * vl_dim1 + 1], &ione, &cs, &sn );
                vl[k + (i__ + 1) * vl_dim1] = 0.;
            }
        }
    }

    if (wantvr) {
        /*
         * Undo balancing of right eigenvectors
         *   (Workspace: need N)
         */
        lapackf77_dgebak("B", "R", &n, &ilo, &ihi, &work[ibal], &n,
                         &vr[vr_offset], &ldvr, &ierr);

        /* Normalize right eigenvectors and make largest component real */
        for (i__ = 1; i__ <= n; ++i__) {
            if (WI[i__-1] == 0.) {
                scl = 1. / magma_cblas_dnrm2(n, &vr[i__ * vr_dim1 + 1], 1);
                blasf77_dscal( &n, &scl, &vr[i__ * vr_dim1 + 1], &ione );
            } else if (WI[i__-1] > 0.) {
                d__1 = magma_cblas_dnrm2(n, &vr[ i__      * vr_dim1 + 1], 1);
                d__2 = magma_cblas_dnrm2(n, &vr[(i__ + 1) * vr_dim1 + 1], 1);
                scl = lapackf77_dlapy2(&d__1, &d__2);
                scl = 1. / scl;
                blasf77_dscal( &n, &scl, &vr[ i__      * vr_dim1 + 1], &ione );
                blasf77_dscal( &n, &scl, &vr[(i__ + 1) * vr_dim1 + 1], &ione );
                i__2 = n;
                for (k = 1; k <= i__2; ++k) {
                    /* Computing 2nd power */
                    d__1 = vr[k + i__ * vr_dim1];
                    /* Computing 2nd power */
                    d__2 = vr[k + (i__ + 1) * vr_dim1];
                    work[iwrk + k - 1] = d__1 * d__1 + d__2 * d__2;
                }
                /* Comment:
                   Fortran BLAS does not have to add 1
                   C       BLAS must add one to cblas_idamax */
                k = blasf77_idamax( &n, &work[iwrk], &ione );  //+1;
                lapackf77_dlartg(&vr[k + i__ * vr_dim1], &vr[k + (i__ + 1) * vr_dim1],
                        &cs, &sn, &r__);
                blasf77_drot( &n, &vr[ i__      * vr_dim1 + 1], &ione,
                                  &vr[(i__ + 1) * vr_dim1 + 1], &ione, &cs, &sn );
                vr[k + (i__ + 1) * vr_dim1] = 0.;
            }
        }
    }

    /*  Undo scaling if necessary */
L50:
    if (scalea) {
        i__1 = n - *info;
        /* Computing MAX */
        i__3 = n - *info;
        i__2 = max(i__3,1);
        lapackf77_dlascl("G", &c__0, &c__0, &cscale, &anrm, &i__1, &c__1,
                         WR + (*info), &i__2, &ierr);
        i__1 = n - *info;
        /* Computing MAX */
        i__3 = n - *info;
        i__2 = max(i__3,1);
        lapackf77_dlascl("G", &c__0, &c__0, &cscale, &anrm, &i__1, &c__1,
                WI + (*info), &i__2, &ierr);
        if (*info > 0) {
            i__1 = ilo - 1;
            lapackf77_dlascl("G", &c__0, &c__0, &cscale, &anrm, &i__1, &c__1,
                    WR, &n, &ierr);
            i__1 = ilo - 1;
            lapackf77_dlascl("G", &c__0, &c__0, &cscale, &anrm, &i__1, &c__1,
                    WI, &n, &ierr);
        }
    }

#if defined(VERSION3)
    magma_free( dT );
#endif
    return *info;
} /* magma_dgeev */
Example #3
0
// ----------------------------------------
int main( int argc, char** argv )
{
    TESTING_INIT();
    
    //real_Double_t   t_m, t_c, t_f;
    magma_int_t ione = 1;
    
    double  *A, *B;
    double diff, error;
    magma_int_t ISEED[4] = {0,0,0,1};
    magma_int_t m, n, k, size, maxn, ld;
    double x2_m, x2_c;  // real x for magma, cblas/fortran blas respectively
    double x_m, x_c;  // x for magma, cblas/fortran blas respectively
    
    magma_opts opts;
    parse_opts( argc, argv, &opts );
    
    opts.tolerance = max( 100., opts.tolerance );
    double tol = opts.tolerance * lapackf77_dlamch("E");
    gTol = tol;
    
    printf( "!! Calling these CBLAS and Fortran BLAS sometimes crashes (segfault), which !!\n"
            "!! is why we use wrappers. It does not necesarily indicate a bug in MAGMA.  !!\n"
            "\n"
            "Diff  compares MAGMA wrapper        to CBLAS and BLAS function; should be exactly 0.\n"
            "Error compares MAGMA implementation to CBLAS and BLAS function; should be ~ machine epsilon.\n"
            "\n" );
    
    double total_diff  = 0.;
    double total_error = 0.;
    int inc[] = { 1 };  //{ -2, -1, 1, 2 };  //{ 1 };  //{ -1, 1 };
    int ninc = sizeof(inc)/sizeof(*inc);
    
    for( int itest = 0; itest < opts.ntest; ++itest ) {
        m = opts.msize[itest];
        n = opts.nsize[itest];
        k = opts.ksize[itest];
        
    for( int iincx = 0; iincx < ninc; ++iincx ) {
        magma_int_t incx = inc[iincx];
        
    for( int iincy = 0; iincy < ninc; ++iincy ) {
        magma_int_t incy = inc[iincy];
        
        printf("=========================================================================\n");
        printf( "m=%d, n=%d, k=%d, incx = %d, incy = %d\n",
                (int) m, (int) n, (int) k, (int) incx, (int) incy );
        printf( "Function              MAGMA     CBLAS     BLAS        Diff      Error\n"
                "                      msec      msec      msec\n" );
        
        // allocate matrices
        // over-allocate so they can be any combination of
        // {m,n,k} * {abs(incx), abs(incy)} by
        // {m,n,k} * {abs(incx), abs(incy)}
        maxn = max( max( m, n ), k ) * max( abs(incx), abs(incy) );
        ld = max( 1, maxn );
        size = ld*maxn;
        magma_dmalloc_pinned( &A,  size );  assert( A   != NULL );
        magma_dmalloc_pinned( &B,  size );  assert( B   != NULL );
        
        // initialize matrices
        lapackf77_dlarnv( &ione, ISEED, &size, A );
        lapackf77_dlarnv( &ione, ISEED, &size, B );
        
        printf( "Level 1 BLAS ----------------------------------------------------------\n" );
        
        
        // ----- test DASUM
        // get one-norm of column j of A
        if ( incx > 0 && incx == incy ) {  // positive, no incy
            diff  = 0;
            error = 0;
            for( int j = 0; j < k; ++j ) {
                x_m = magma_cblas_dasum( m, A(0,j), incx );
                
                x_c = cblas_dasum( m, A(0,j), incx );
                diff += fabs( x_m - x_c );
                
                x_c = blasf77_dasum( &m, A(0,j), &incx );
                error += fabs( (x_m - x_c) / (m*x_c) );
            }
            output( "dasum", diff, error );
            total_diff  += diff;
            total_error += error;
        }
        
        // ----- test DNRM2
        // get two-norm of column j of A
        if ( incx > 0 && incx == incy ) {  // positive, no incy
            diff  = 0;
            error = 0;
            for( int j = 0; j < k; ++j ) {
                x_m = magma_cblas_dnrm2( m, A(0,j), incx );
                
                x_c = cblas_dnrm2( m, A(0,j), incx );
                diff += fabs( x_m - x_c );
                
                x_c = blasf77_dnrm2( &m, A(0,j), &incx );
                error += fabs( (x_m - x_c) / (m*x_c) );
            }
            output( "dnrm2", diff, error );
            total_diff  += diff;
            total_error += error;
        }
        
        // ----- test DDOT
        // dot columns, Aj^H Bj
        diff  = 0;
        error = 0;
        for( int j = 0; j < k; ++j ) {
            // MAGMA implementation, not just wrapper
            x2_m = magma_cblas_ddot( m, A(0,j), incx, B(0,j), incy );
            
            // crashes on MKL 11.1.2, ILP64
            #if ! defined( MAGMA_WITH_MKL )
                #ifdef COMPLEX
                cblas_ddot_sub( m, A(0,j), incx, B(0,j), incy, &x2_c );
                #else
                x2_c = cblas_ddot( m, A(0,j), incx, B(0,j), incy );
                #endif
                error += fabs( x2_m - x2_c ) / fabs( m*x2_c );
            #endif
            
            // crashes on MacOS 10.9
            #if ! defined( __APPLE__ )
                x2_c = blasf77_ddot( &m, A(0,j), &incx, B(0,j), &incy );
                error += fabs( x2_m - x2_c ) / fabs( m*x2_c );
            #endif
        }
        output( "ddot", diff, error );
        total_diff  += diff;
        total_error += error;
        total_error += error;
        
        // ----- test DDOT
        // dot columns, Aj^T * Bj
        diff  = 0;
        error = 0;
        for( int j = 0; j < k; ++j ) {
            // MAGMA implementation, not just wrapper
            x2_m = magma_cblas_ddot( m, A(0,j), incx, B(0,j), incy );
            
            // crashes on MKL 11.1.2, ILP64
            #if ! defined( MAGMA_WITH_MKL )
                #ifdef COMPLEX
                cblas_ddot_sub( m, A(0,j), incx, B(0,j), incy, &x2_c );
                #else
                x2_c = cblas_ddot( m, A(0,j), incx, B(0,j), incy );
                #endif
                error += fabs( x2_m - x2_c ) / fabs( m*x2_c );
            #endif
            
            // crashes on MacOS 10.9
            #if ! defined( __APPLE__ )
                x2_c = blasf77_ddot( &m, A(0,j), &incx, B(0,j), &incy );
                error += fabs( x2_m - x2_c ) / fabs( m*x2_c );
            #endif
        }
        output( "ddot", diff, error );
        total_diff  += diff;
        total_error += error;
        
        // tell user about disabled functions
        #if defined( MAGMA_WITH_MKL )
            printf( "cblas_ddot and cblas_ddot disabled with MKL (segfaults)\n" );
        #endif
        
        #if defined( __APPLE__ )
            printf( "blasf77_ddot and blasf77_ddot disabled on MacOS (segfaults)\n" );
        #endif
            
        // cleanup
        magma_free_pinned( A );
        magma_free_pinned( B );
        fflush( stdout );
    }}}  // itest, incx, incy
    
    // TODO use average error?
    printf( "sum diffs  = %8.2g, MAGMA wrapper        compared to CBLAS and Fortran BLAS; should be exactly 0.\n"
            "sum errors = %8.2e, MAGMA implementation compared to CBLAS and Fortran BLAS; should be ~ machine epsilon.\n\n",
            total_diff, total_error );
    if ( total_diff != 0. ) {
        printf( "some tests failed diff == 0.; see above.\n" );
    }
    else {
        printf( "all tests passed diff == 0.\n" );
    }
    
    TESTING_FINALIZE();
    
    int status = (total_diff != 0.);
    return status;
}
Example #4
0
/**
    Purpose
    -------
    DGEQP3 computes a QR factorization with column pivoting of a
    matrix A:  A*P = Q*R  using Level 3 BLAS.

    Arguments
    ---------
    @param[in]
    m       INTEGER
            The number of rows of the matrix A. M >= 0.

    @param[in]
    n       INTEGER
            The number of columns of the matrix A.  N >= 0.

    @param[in,out]
    A       DOUBLE_PRECISION array, dimension (LDA,N)
            On entry, the M-by-N matrix A.
            On exit, the upper triangle of the array contains the
            min(M,N)-by-N upper trapezoidal matrix R; the elements below
            the diagonal, together with the array TAU, represent the
            unitary matrix Q as a product of min(M,N) elementary
            reflectors.

    @param[in]
    lda     INTEGER
            The leading dimension of the array A. LDA >= max(1,M).

    @param[in,out]
    jpvt    INTEGER array, dimension (N)
            On entry, if JPVT(J).ne.0, the J-th column of A is permuted
            to the front of A*P (a leading column); if JPVT(J)=0,
            the J-th column of A is a free column.
            On exit, if JPVT(J)=K, then the J-th column of A*P was the
            the K-th column of A.

    @param[out]
    tau     DOUBLE_PRECISION array, dimension (min(M,N))
            The scalar factors of the elementary reflectors.

    @param[out]
    work    (workspace) DOUBLE_PRECISION array, dimension (MAX(1,LWORK))
            On exit, if INFO=0, WORK[0] returns the optimal LWORK.

    @param[in]
    lwork   INTEGER
            The dimension of the array WORK.
            For [sd]geqp3, LWORK >= (N+1)*NB + 2*N;
            for [cz]geqp3, LWORK >= (N+1)*NB,
            where NB is the optimal blocksize.
    \n
            If LWORK = -1, then a workspace query is assumed; the routine
            only calculates the optimal size of the WORK array, returns
            this value as the first entry of the WORK array, and no error
            message related to LWORK is issued by XERBLA.

    @param
    rwork   (workspace, for [cz]geqp3 only) DOUBLE PRECISION array, dimension (2*N)

    @param[out]
    info    INTEGER
      -     = 0: successful exit.
      -     < 0: if INFO = -i, the i-th argument had an illegal value.

    Further Details
    ---------------
    The matrix Q is represented as a product of elementary reflectors

      Q = H(1) H(2) . . . H(k), where k = min(m,n).

    Each H(i) has the form

      H(i) = I - tau * v * v'

    where tau is a real scalar, and v is a real vector
    with v(1:i-1) = 0 and v(i) = 1; v(i+1:m) is stored on exit in
    A(i+1:m,i), and tau in TAU(i).

    @ingroup magma_dgeqp3_comp
    ********************************************************************/
extern "C" magma_int_t
magma_dgeqp3(
    magma_int_t m, magma_int_t n,
    double *A, magma_int_t lda,
    magma_int_t *jpvt, double *tau,
    double *work, magma_int_t lwork,
    #ifdef COMPLEX
    double *rwork,
    #endif
    magma_int_t *info )
{
#define  A(i, j) (A     + (i) + (j)*(lda ))
#define dA(i, j) (dwork + (i) + (j)*(ldda))

    double   *dwork, *df;

    magma_int_t ione = 1;

    magma_int_t n_j, ldda, ldwork;
    magma_int_t j, jb, na, nb, sm, sn, fjb, nfxd, minmn;
    magma_int_t topbmn, sminmn, lwkopt=0, lquery;
    
    *info = 0;
    lquery = (lwork == -1);
    if (m < 0) {
        *info = -1;
    } else if (n < 0) {
        *info = -2;
    } else if (lda < max(1,m)) {
        *info = -4;
    }
    
    nb = magma_get_dgeqp3_nb(min(m, n));
    minmn = min(m,n);
    if (*info == 0) {
        if (minmn == 0) {
            lwkopt = 1;
        } else {
            lwkopt = (n + 1)*nb;
            #ifdef REAL
            lwkopt += 2*n;
            #endif
        }
        work[0] = MAGMA_D_MAKE( lwkopt, 0. );

        if (lwork < lwkopt && ! lquery) {
            *info = -8;
        }
    }

    if (*info != 0) {
        magma_xerbla( __func__, -(*info) );
        return *info;
    } else if (lquery) {
        return *info;
    }

    if (minmn == 0)
        return *info;

    #ifdef REAL
    double *rwork = work + (n + 1)*nb;
    #endif

    ldda = ((m+31)/32)*32;
    ldwork = n*ldda + (n+1)*nb;
    if (MAGMA_SUCCESS != magma_dmalloc( &dwork, ldwork )) {
        *info = MAGMA_ERR_DEVICE_ALLOC;
        return *info;
    }
    df = dwork + n*ldda;
    // dwork used for dA

    magma_queue_t stream;
    magma_queue_create( &stream );

    /* Move initial columns up front.
     * Note jpvt uses 1-based indices for historical compatibility. */
    nfxd = 0;
    for (j = 0; j < n; ++j) {
        if (jpvt[j] != 0) {
            if (j != nfxd) {
                blasf77_dswap(&m, A(0, j), &ione, A(0, nfxd), &ione);
                jpvt[j]    = jpvt[nfxd];
                jpvt[nfxd] = j + 1;
            }
            else {
                jpvt[j] = j + 1;
            }
            ++nfxd;
        }
        else {
            jpvt[j] = j + 1;
        }
    }

    /*     Factorize fixed columns
           =======================
           Compute the QR factorization of fixed columns and update
           remaining columns. */
    if (nfxd > 0) {
        na = min(m,nfxd);
        lapackf77_dgeqrf(&m, &na, A, &lda, tau, work, &lwork, info);
        if (na < n) {
            n_j = n - na;
            lapackf77_dormqr( MagmaLeftStr, MagmaConjTransStr, &m, &n_j, &na,
                              A, &lda, tau, A(0, na), &lda,
                              work, &lwork, info );
        }
    }
    
    /*  Factorize free columns */
    if (nfxd < minmn) {
        sm = m - nfxd;
        sn = n - nfxd;
        sminmn = minmn - nfxd;
        
        if (nb < sminmn) {
            j = nfxd;
            
            // Set the original matrix to the GPU
            magma_dsetmatrix_async( m, sn,
                                    A (0,j), lda,
                                    dA(0,j), ldda, stream );
        }

        /* Initialize partial column norms. */
        for (j = nfxd; j < n; ++j) {
            rwork[j] = magma_cblas_dnrm2( sm, A(nfxd,j), ione );
            rwork[n + j] = rwork[j];
        }
        
        j = nfxd;
        if (nb < sminmn) {
            /* Use blocked code initially. */
            magma_queue_sync( stream );
            
            /* Compute factorization: while loop. */
            topbmn = minmn - nb;
            while(j < topbmn) {
                jb = min(nb, topbmn - j);
                
                /* Factorize JB columns among columns J:N. */
                n_j = n - j;
                
                if (j > nfxd) {
                    // Get panel to the CPU
                    magma_dgetmatrix( m-j, jb,
                                      dA(j,j), ldda,
                                      A (j,j), lda );
                    
                    // Get the rows
                    magma_dgetmatrix( jb, n_j - jb,
                                      dA(j,j + jb), ldda,
                                      A (j,j + jb), lda );
                }

                magma_dlaqps( m, n_j, j, jb, &fjb,
                              A (0, j), lda,
                              dA(0, j), ldda,
                              &jpvt[j], &tau[j], &rwork[j], &rwork[n + j],
                              work,
                              &work[jb], n_j,
                              &df[jb],   n_j );
                
                j += fjb;  /* fjb is actual number of columns factored */
            }
        }
        
        /* Use unblocked code to factor the last or only block. */
        if (j < minmn) {
            n_j = n - j;
            if (j > nfxd) {
                magma_dgetmatrix( m-j, n_j,
                                  dA(j,j), ldda,
                                  A (j,j), lda );
            }
            lapackf77_dlaqp2(&m, &n_j, &j, A(0, j), &lda, &jpvt[j],
                             &tau[j], &rwork[j], &rwork[n+j], work );
        }
    }

    work[0] = MAGMA_D_MAKE( lwkopt, 0. );
    magma_free( dwork );

    magma_queue_destroy( stream );

    return *info;
} /* magma_dgeqp3 */
Example #5
0
/* ////////////////////////////////////////////////////////////////////////////
   -- Testing dgeev
*/
int main( int argc, char** argv)
{
    TESTING_INIT();

    real_Double_t   gpu_time, cpu_time;
    double *h_A, *h_R, *VL, *VR, *h_work, *w1, *w2;
    double *w1i, *w2i;
    magmaDoubleComplex *w1copy, *w2copy;
    magmaDoubleComplex  c_neg_one = MAGMA_Z_NEG_ONE;
    double tnrm, result[9];
    magma_int_t N, n2, lda, nb, lwork, info;
    magma_int_t ione     = 1;
    magma_int_t ISEED[4] = {0,0,0,1};
    double ulp, ulpinv, error;
    magma_int_t status = 0;

    ulp = lapackf77_dlamch( "P" );
    ulpinv = 1./ulp;

    magma_opts opts;
    parse_opts( argc, argv, &opts );

    // need slightly looser bound (60*eps instead of 30*eps) for some tests
    opts.tolerance = max( 60., opts.tolerance );
    double tol    = opts.tolerance * lapackf77_dlamch("E");
    double tolulp = opts.tolerance * lapackf77_dlamch("P");

    // enable at least some minimal checks, if requested
    if ( opts.check && !opts.lapack && opts.jobvl == MagmaNoVec && opts.jobvr == MagmaNoVec ) {
        fprintf( stderr, "NOTE: Some checks require vectors to be computed;\n"
                 "      set jobvl=V (option -LV), or jobvr=V (option -RV), or both.\n"
                 "      Some checks require running lapack (-l); setting lapack.\n\n");
        opts.lapack = true;
    }

    printf("    N   CPU Time (sec)   GPU Time (sec)   |W_magma - W_lapack| / |W_lapack|\n");
    printf("===========================================================================\n");
    for( int itest = 0; itest < opts.ntest; ++itest ) {
        for( int iter = 0; iter < opts.niter; ++iter ) {
            N = opts.nsize[itest];
            lda   = N;
            n2    = lda*N;
            nb    = magma_get_dgehrd_nb(N);
            lwork = N*(2 + nb);
            // generous workspace - required by dget22
            lwork = max( lwork, N*(5 + 2*N) );

            TESTING_MALLOC_CPU( w1copy, magmaDoubleComplex, N );
            TESTING_MALLOC_CPU( w2copy, magmaDoubleComplex, N );
            TESTING_MALLOC_CPU( w1,  double, N  );
            TESTING_MALLOC_CPU( w2,  double, N  );
            TESTING_MALLOC_CPU( w1i, double, N  );
            TESTING_MALLOC_CPU( w2i, double, N  );
            TESTING_MALLOC_CPU( h_A, double, n2 );

            TESTING_MALLOC_PIN( h_R, double, n2 );
            TESTING_MALLOC_PIN( VL,  double, n2 );
            TESTING_MALLOC_PIN( VR,  double, n2 );
            TESTING_MALLOC_PIN( h_work, double, lwork );

            /* Initialize the matrix */
            lapackf77_dlarnv( &ione, ISEED, &n2, h_A );
            lapackf77_dlacpy( MagmaUpperLowerStr, &N, &N, h_A, &lda, h_R, &lda );

            /* ====================================================================
               Performs operation using MAGMA
               =================================================================== */
            gpu_time = magma_wtime();
            magma_dgeev( opts.jobvl, opts.jobvr,
                         N, h_R, lda, w1, w1i,
                         VL, lda, VR, lda,
                         h_work, lwork, opts.queue, &info );
            gpu_time = magma_wtime() - gpu_time;
            if (info != 0)
                printf("magma_dgeev returned error %d: %s.\n",
                       (int) info, magma_strerror( info ));

            /* =====================================================================
               Check the result
               =================================================================== */
            if ( opts.check ) {
                /* ===================================================================
                 * Check the result following LAPACK's [zcds]drvev routine.
                 * The following tests are performed:
                 * (1)   | A * VR - VR * W | / ( n |A| )
                 *
                 *       Here VR is the matrix of unit right eigenvectors.
                 *       W is a diagonal matrix with diagonal entries W(j).
                 *
                 * (2)   | |VR(i)| - 1 |   and whether largest component real
                 *
                 *       VR(i) denotes the i-th column of VR.
                 *
                 * (3)   | A**T * VL - VL * W**T | / ( n |A| )
                 *
                 *       Here VL is the matrix of unit left eigenvectors, A**T is the
                 *       transpose of A, and W is as above.
                 *
                 * (4)   | |VL(i)| - 1 |   and whether largest component real
                 *
                 *       VL(i) denotes the i-th column of VL.
                 *
                 * (5)   W(full) = W(partial, W only) -- currently skipped
                 * (6)   W(full) = W(partial, W and VR)
                 * (7)   W(full) = W(partial, W and VL)
                 *
                 *       W(full) denotes the eigenvalues computed when both VR and VL
                 *       are also computed, and W(partial) denotes the eigenvalues
                 *       computed when only W, only W and VR, or only W and VL are
                 *       computed.
                 *
                 * (8)   VR(full) = VR(partial, W and VR)
                 *
                 *       VR(full) denotes the right eigenvectors computed when both VR
                 *       and VL are computed, and VR(partial) denotes the result
                 *       when only VR is computed.
                 *
                 * (9)   VL(full) = VL(partial, W and VL)
                 *
                 *       VL(full) denotes the left eigenvectors computed when both VR
                 *       and VL are also computed, and VL(partial) denotes the result
                 *       when only VL is computed.
                 *
                 * (1, 2) only if jobvr = V
                 * (3, 4) only if jobvl = V
                 * (5-9)  only if check = 2 (option -c2)
                 ================================================================= */
                double vmx, vrmx, vtst;

                // Initialize result. -1 indicates test was not run.
                for( int j = 0; j < 9; ++j )
                    result[j] = -1.;

                if ( opts.jobvr == MagmaVec ) {
                    // Do test 1: | A * VR - VR * W | / ( n |A| )
                    // Note this writes result[1] also
                    lapackf77_dget22( MagmaNoTransStr, MagmaNoTransStr, MagmaNoTransStr,
                                      &N, h_A, &lda, VR, &lda, w1, w1i,
                                      h_work, &result[0] );
                    result[0] *= ulp;

                    // Do test 2: | |VR(i)| - 1 |   and whether largest component real
                    result[1] = -1.;
                    for( int j = 0; j < N; ++j ) {
                        tnrm = 1.;
                        if (w1i[j] == 0.)
                            tnrm = magma_cblas_dnrm2( N, &VR[j*lda], ione );
                        else if (w1i[j] > 0.)
                            tnrm = magma_dlapy2( magma_cblas_dnrm2( N, &VR[j*lda],     ione ),
                                                 magma_cblas_dnrm2( N, &VR[(j+1)*lda], ione ));

                        result[1] = max( result[1], min( ulpinv, MAGMA_D_ABS(tnrm-1.)/ulp ));

                        if (w1i[j] > 0.) {
                            vmx  = vrmx = 0.;
                            for( int jj = 0; jj < N; ++jj ) {
                                vtst = magma_dlapy2( VR[jj+j*lda], VR[jj+(j+1)*lda]);
                                if (vtst > vmx)
                                    vmx = vtst;

                                if ( (VR[jj + (j+1)*lda])==0. &&
                                        MAGMA_D_ABS( VR[jj+j*lda] ) > vrmx)
                                {
                                    vrmx = MAGMA_D_ABS( VR[jj+j*lda] );
                                }
                            }
                            if (vrmx / vmx < 1. - ulp*2.)
                                result[1] = ulpinv;
                        }
                    }
                    result[1] *= ulp;
                }

                if ( opts.jobvl == MagmaVec ) {
                    // Do test 3: | A**T * VL - VL * W**T | / ( n |A| )
                    // Note this writes result[3] also
                    lapackf77_dget22( MagmaTransStr, MagmaNoTransStr, MagmaTransStr,
                                      &N, h_A, &lda, VL, &lda, w1, w1i,
                                      h_work, &result[2] );
                    result[2] *= ulp;

                    // Do test 4: | |VL(i)| - 1 |   and whether largest component real
                    result[3] = -1.;
                    for( int j = 0; j < N; ++j ) {
                        tnrm = 1.;
                        if (w1i[j] == 0.)
                            tnrm = magma_cblas_dnrm2( N, &VL[j*lda], ione );
                        else if (w1i[j] > 0.)
                            tnrm = magma_dlapy2( magma_cblas_dnrm2( N, &VL[j*lda],     ione ),
                                                 magma_cblas_dnrm2( N, &VL[(j+1)*lda], ione ));

                        result[3] = max( result[3], min( ulpinv, MAGMA_D_ABS(tnrm-1.)/ulp ));

                        if (w1i[j] > 0.) {
                            vmx  = vrmx = 0.;
                            for( int jj = 0; jj < N; ++jj ) {
                                vtst = magma_dlapy2( VL[jj+j*lda], VL[jj+(j+1)*lda]);
                                if (vtst > vmx)
                                    vmx = vtst;

                                if ( (VL[jj + (j+1)*lda])==0. &&
                                        MAGMA_D_ABS( VL[jj+j*lda]) > vrmx)
                                {
                                    vrmx = MAGMA_D_ABS( VL[jj+j*lda] );
                                }
                            }
                            if (vrmx / vmx < 1. - ulp*2.)
                                result[3] = ulpinv;
                        }
                    }
                    result[3] *= ulp;
                }
            }
            if ( opts.check == 2 ) {
                // more extensive tests
                // this is really slow because it calls magma_zgeev multiple times
                double *LRE, DUM;
                TESTING_MALLOC_PIN( LRE, double, n2 );

                lapackf77_dlarnv( &ione, ISEED, &n2, h_A );
                lapackf77_dlacpy( MagmaUpperLowerStr, &N, &N, h_A, &lda, h_R, &lda );

                // ----------
                // Compute eigenvalues, left and right eigenvectors
                magma_dgeev( MagmaVec, MagmaVec,
                             N, h_R, lda, w1, w1i,
                             VL, lda, VR, lda,
                             h_work, lwork, opts.queue, &info );
                if (info != 0)
                    printf("magma_zgeev (case V, V) returned error %d: %s.\n",
                           (int) info, magma_strerror( info ));

                // ----------
                // Compute eigenvalues only
                // These are not exactly equal, and not in the same order, so skip for now.
                //lapackf77_dlacpy( MagmaUpperLowerStr, &N, &N, h_A, &lda, h_R, &lda );
                //magma_dgeev( MagmaNoVec, MagmaNoVec,
                //             N, h_R, lda, w2, w2i,
                //             &DUM, 1, &DUM, 1,
                //             h_work, lwork, opts.queue, &info );
                //if (info != 0)
                //    printf("magma_dgeev (case N, N) returned error %d: %s.\n",
                //           (int) info, magma_strerror( info ));
                //
                //// Do test 5: W(full) = W(partial, W only)
                //result[4] = 1;
                //for( int j = 0; j < N; ++j )
                //    if ( w1[j] != w2[j] || w1i[j] != w2i[j] )
                //        result[4] = 0;

                // ----------
                // Compute eigenvalues and right eigenvectors
                lapackf77_dlacpy( MagmaUpperLowerStr, &N, &N, h_A, &lda, h_R, &lda );
                magma_dgeev( MagmaNoVec, MagmaVec,
                             N, h_R, lda, w2, w2i,
                             &DUM, 1, LRE, lda,
                             h_work, lwork, opts.queue, &info );
                if (info != 0)
                    printf("magma_dgeev (case N, V) returned error %d: %s.\n",
                           (int) info, magma_strerror( info ));

                // Do test 6: W(full) = W(partial, W and VR)
                result[5] = 1;
                for( int j = 0; j < N; ++j )
                    if ( w1[j] != w2[j] || w1i[j] != w2i[j] )
                        result[5] = 0;

                // Do test 8: VR(full) = VR(partial, W and VR)
                result[7] = 1;
                for( int j = 0; j < N; ++j )
                    for( int jj = 0; jj < N; ++jj )
                        if ( ! MAGMA_D_EQUAL( VR[j+jj*lda], LRE[j+jj*lda] ))
                            result[7] = 0;

                // ----------
                // Compute eigenvalues and left eigenvectors
                lapackf77_dlacpy( MagmaUpperLowerStr, &N, &N, h_A, &lda, h_R, &lda );
                magma_dgeev( MagmaVec, MagmaNoVec,
                             N, h_R, lda, w2, w2i,
                             LRE, lda, &DUM, 1,
                             h_work, lwork, opts.queue, &info );
                if (info != 0)
                    printf("magma_dgeev (case V, N) returned error %d: %s.\n",
                           (int) info, magma_strerror( info ));

                // Do test 7: W(full) = W(partial, W and VL)
                result[6] = 1;
                for( int j = 0; j < N; ++j )
                    if ( w1[j] != w2[j] || w1i[j] != w2i[j] )
                        result[6] = 0;

                // Do test 9: VL(full) = VL(partial, W and VL)
                result[8] = 1;
                for( int j = 0; j < N; ++j )
                    for( int jj = 0; jj < N; ++jj )
                        if ( ! MAGMA_D_EQUAL( VL[j+jj*lda], LRE[j+jj*lda] ))
                            result[8] = 0;

                TESTING_FREE_PIN( LRE );
            }

            /* =====================================================================
               Performs operation using LAPACK
               Do this after checks, because it overwrites VL and VR.
               =================================================================== */
            if ( opts.lapack ) {
                cpu_time = magma_wtime();
                lapackf77_dgeev( lapack_vec_const(opts.jobvl), lapack_vec_const(opts.jobvr),
                                 &N, h_A, &lda, w2, w2i,
                                 VL, &lda, VR, &lda,
                                 h_work, &lwork, &info );
                cpu_time = magma_wtime() - cpu_time;
                if (info != 0)
                    printf("lapackf77_dgeev returned error %d: %s.\n",
                           (int) info, magma_strerror( info ));

                // check | W_magma - W_lapack | / | W |
                // need to sort eigenvalues first
                // copy them into complex vectors for ease
                for( int j=0; j < N; ++j ) {
                    w1copy[j] = MAGMA_Z_MAKE( w1[j], w1i[j] );
                    w2copy[j] = MAGMA_Z_MAKE( w2[j], w2i[j] );
                }
                std::sort( w1copy, &w1copy[N], lessthan );
                std::sort( w2copy, &w2copy[N], lessthan );

                // adjust sorting to deal with numerical inaccuracy
                // search down w2 for eigenvalue that matches w1's eigenvalue
                for( int j=0; j < N; ++j ) {
                    for( int j2=j; j2 < N; ++j2 ) {
                        magmaDoubleComplex diff = MAGMA_Z_SUB( w1copy[j], w2copy[j2] );
                        double diff2 = magma_dzlapy2( diff ) / max( magma_dzlapy2( w1copy[j] ), tol );
                        if ( diff2 < 100*tol ) {
                            if ( j != j2 ) {
                                std::swap( w2copy[j], w2copy[j2] );
                            }
                            break;
                        }
                    }
                }

                blasf77_zaxpy( &N, &c_neg_one, w2copy, &ione, w1copy, &ione );
                error  = magma_cblas_dznrm2( N, w1copy, 1 );
                error /= magma_cblas_dznrm2( N, w2copy, 1 );

                printf("%5d   %7.2f          %7.2f          %8.2e   %s\n",
                       (int) N, cpu_time, gpu_time,
                       error, (error < tolulp ? "ok" : "failed"));
                status += ! (error < tolulp);
            }
            else {
                printf("%5d     ---            %7.2f\n",
                       (int) N, gpu_time);
            }
            if ( opts.check ) {
                // -1 indicates test was not run
                if ( result[0] != -1 ) {
                    printf("        | A * VR - VR * W | / ( n |A| ) = %8.2e   %s\n", result[0], (result[0] < tol ? "ok" : "failed"));
                }
                if ( result[1] != -1 ) {
                    printf("        |  |VR(i)| - 1    |             = %8.2e   %s\n", result[1], (result[1] < tol ? "ok" : "failed"));
                }
                if ( result[2] != -1 ) {
                    printf("        | A'* VL - VL * W'| / ( n |A| ) = %8.2e   %s\n", result[2], (result[2] < tol ? "ok" : "failed"));
                }
                if ( result[3] != -1 ) {
                    printf("        |  |VL(i)| - 1    |             = %8.2e   %s\n", result[3], (result[3] < tol ? "ok" : "failed"));
                }
                if ( result[4] != -1 ) {
                    printf("        W  (full) == W  (partial, W only)           %s\n",         (result[4] == 1. ? "ok" : "failed"));
                }
                if ( result[5] != -1 ) {
                    printf("        W  (full) == W  (partial, W and VR)         %s\n",         (result[5] == 1. ? "ok" : "failed"));
                }
                if ( result[6] != -1 ) {
                    printf("        W  (full) == W  (partial, W and VL)         %s\n",         (result[6] == 1. ? "ok" : "failed"));
                }
                if ( result[7] != -1 ) {
                    printf("        VR (full) == VR (partial, W and VR)         %s\n",         (result[7] == 1. ? "ok" : "failed"));
                }
                if ( result[8] != -1 ) {
                    printf("        VL (full) == VL (partial, W and VL)         %s\n",         (result[8] == 1. ? "ok" : "failed"));
                }

                int newline = 0;
                if ( result[0] != -1 ) {
                    status += ! (result[0] < tol);
                    newline = 1;
                }
                if ( result[1] != -1 ) {
                    status += ! (result[1] < tol);
                    newline = 1;
                }
                if ( result[2] != -1 ) {
                    status += ! (result[2] < tol);
                    newline = 1;
                }
                if ( result[3] != -1 ) {
                    status += ! (result[3] < tol);
                    newline = 1;
                }
                if ( result[4] != -1 ) {
                    status += ! (result[4] == 1.);
                    newline = 1;
                }
                if ( result[5] != -1 ) {
                    status += ! (result[5] == 1.);
                    newline = 1;
                }
                if ( result[6] != -1 ) {
                    status += ! (result[6] == 1.);
                    newline = 1;
                }
                if ( result[7] != -1 ) {
                    status += ! (result[7] == 1.);
                    newline = 1;
                }
                if ( result[8] != -1 ) {
                    status += ! (result[8] == 1.);
                    newline = 1;
                }
                if ( newline ) {
                    printf( "\n" );
                }
            }

            TESTING_FREE_CPU( w1copy );
            TESTING_FREE_CPU( w2copy );
            TESTING_FREE_CPU( w1  );
            TESTING_FREE_CPU( w2  );
            TESTING_FREE_CPU( w1i );
            TESTING_FREE_CPU( w2i );
            TESTING_FREE_CPU( h_A );

            TESTING_FREE_PIN( h_R );
            TESTING_FREE_PIN( VL  );
            TESTING_FREE_PIN( VR  );
            TESTING_FREE_PIN( h_work );
            fflush( stdout );
        }
        if ( opts.niter > 1 ) {
            printf( "\n" );
        }
    }

    TESTING_FINALIZE();
    return status;
}
Example #6
0
/**
    Purpose
    -------
    DGEEV computes for an N-by-N real nonsymmetric matrix A, the
    eigenvalues and, optionally, the left and/or right eigenvectors.

    The right eigenvector v(j) of A satisfies
                     A * v(j) = lambda(j) * v(j)
    where lambda(j) is its eigenvalue.
    The left eigenvector u(j) of A satisfies
                  u(j)**T * A = lambda(j) * u(j)**T
    where u(j)**T denotes the transpose of u(j).

    The computed eigenvectors are normalized to have Euclidean norm
    equal to 1 and largest component real.

    Arguments
    ---------
    @param[in]
    jobvl   magma_vec_t
      -     = MagmaNoVec: left eigenvectors of A are not computed;
      -     = MagmaVec:   left eigenvectors of are computed.

    @param[in]
    jobvr   magma_vec_t
      -     = MagmaNoVec: right eigenvectors of A are not computed;
      -     = MagmaVec:   right eigenvectors of A are computed.

    @param[in]
    n       INTEGER
            The order of the matrix A. N >= 0.

    @param[in,out]
    A       DOUBLE PRECISION array, dimension (LDA,N)
            On entry, the N-by-N matrix A.
            On exit, A has been overwritten.

    @param[in]
    lda     INTEGER
            The leading dimension of the array A.  LDA >= max(1,N).

    @param[out]
    wr      DOUBLE PRECISION array, dimension (N)
    @param[out]
    wi      DOUBLE PRECISION array, dimension (N)
            WR and WI contain the real and imaginary parts,
            respectively, of the computed eigenvalues.  Complex
            conjugate pairs of eigenvalues appear consecutively
            with the eigenvalue having the positive imaginary part
            first.

    @param[out]
    VL      DOUBLE PRECISION array, dimension (LDVL,N)
            If JOBVL = MagmaVec, the left eigenvectors u(j) are stored one
            after another in the columns of VL, in the same order
            as their eigenvalues.
            If JOBVL = MagmaNoVec, VL is not referenced.
            u(j) = VL(:,j), the j-th column of VL.

    @param[in]
    ldvl    INTEGER
            The leading dimension of the array VL.  LDVL >= 1; if
            JOBVL = MagmaVec, LDVL >= N.

    @param[out]
    VR      DOUBLE PRECISION array, dimension (LDVR,N)
            If JOBVR = MagmaVec, the right eigenvectors v(j) are stored one
            after another in the columns of VR, in the same order
            as their eigenvalues.
            If JOBVR = MagmaNoVec, VR is not referenced.
            v(j) = VR(:,j), the j-th column of VR.

    @param[in]
    ldvr    INTEGER
            The leading dimension of the array VR.  LDVR >= 1; if
            JOBVR = MagmaVec, LDVR >= N.

    @param[out]
    work    (workspace) DOUBLE PRECISION array, dimension (MAX(1,LWORK))
            On exit, if INFO = 0, WORK[0] returns the optimal LWORK.

    @param[in]
    lwork   INTEGER
            The dimension of the array WORK.  LWORK >= (2+nb)*N.
            For optimal performance, LWORK >= (2+2*nb)*N.
    \n
            If LWORK = -1, then a workspace query is assumed; the routine
            only calculates the optimal size of the WORK array, returns
            this value as the first entry of the WORK array, and no error
            message related to LWORK is issued by XERBLA.

    @param[out]
    info    INTEGER
      -     = 0:  successful exit
      -     < 0:  if INFO = -i, the i-th argument had an illegal value.
      -     > 0:  if INFO = i, the QR algorithm failed to compute all the
                  eigenvalues, and no eigenvectors have been computed;
                  elements and i+1:N of W contain eigenvalues which have
                  converged.

    @ingroup magma_dgeev_driver
    ********************************************************************/
extern "C" magma_int_t
magma_dgeev_m(
    magma_vec_t jobvl, magma_vec_t jobvr, magma_int_t n,
    double *A, magma_int_t lda,
    double *wr, double *wi,
    double *VL, magma_int_t ldvl,
    double *VR, magma_int_t ldvr,
    double *work, magma_int_t lwork,
    magma_int_t *info )
{
    #define VL(i,j)  (VL + (i) + (j)*ldvl)
    #define VR(i,j)  (VR + (i) + (j)*ldvr)
    
    const magma_int_t ione  = 1;
    const magma_int_t izero = 0;
    
    double d__1, d__2;
    double r, cs, sn, scl;
    double dum[1], eps;
    double anrm, cscale, bignum, smlnum;
    magma_int_t i, k, ilo, ihi;
    magma_int_t ibal, ierr, itau, iwrk, nout, liwrk, nb;
    magma_int_t scalea, minwrk, optwrk, lquery, wantvl, wantvr, select[1];
    
    magma_side_t side = MagmaRight;
    
    magma_timer_t time_total=0, time_gehrd=0, time_unghr=0, time_hseqr=0, time_trevc=0, time_sum=0;
    magma_flops_t flop_total=0, flop_gehrd=0, flop_unghr=0, flop_hseqr=0, flop_trevc=0, flop_sum=0;
    timer_start( time_total );
    flops_start( flop_total );
    
    *info = 0;
    lquery = (lwork == -1);
    wantvl = (jobvl == MagmaVec);
    wantvr = (jobvr == MagmaVec);
    if (! wantvl && jobvl != MagmaNoVec) {
        *info = -1;
    } else if (! wantvr && jobvr != MagmaNoVec) {
        *info = -2;
    } else if (n < 0) {
        *info = -3;
    } else if (lda < max(1,n)) {
        *info = -5;
    } else if ( (ldvl < 1) || (wantvl && (ldvl < n))) {
        *info = -9;
    } else if ( (ldvr < 1) || (wantvr && (ldvr < n))) {
        *info = -11;
    }

    /* Compute workspace */
    nb = magma_get_dgehrd_nb( n );
    if (*info == 0) {
        minwrk = (2 +   nb)*n;
        optwrk = (2 + 2*nb)*n;
        work[0] = MAGMA_D_MAKE( (double) optwrk, 0. );
        
        if (lwork < minwrk && ! lquery) {
            *info = -13;
        }
    }

    if (*info != 0) {
        magma_xerbla( __func__, -(*info) );
        return *info;
    }
    else if (lquery) {
        return *info;
    }

    /* Quick return if possible */
    if (n == 0) {
        return *info;
    }
   
    #if defined(Version3) || defined(Version4) || defined(Version5)
    double *dT;
    if (MAGMA_SUCCESS != magma_dmalloc( &dT, nb*n )) {
        *info = MAGMA_ERR_DEVICE_ALLOC;
        return *info;
    }
    #endif
    #if defined(Version4) || defined(Version5)
    double *T;
    if (MAGMA_SUCCESS != magma_dmalloc_cpu( &T, nb*n )) {
        magma_free( dT );
        *info = MAGMA_ERR_HOST_ALLOC;
        return *info;
    }
    #endif

    /* Get machine constants */
    eps    = lapackf77_dlamch( "P" );
    smlnum = lapackf77_dlamch( "S" );
    bignum = 1. / smlnum;
    lapackf77_dlabad( &smlnum, &bignum );
    smlnum = magma_dsqrt( smlnum ) / eps;
    bignum = 1. / smlnum;

    /* Scale A if max element outside range [SMLNUM,BIGNUM] */
    anrm = lapackf77_dlange( "M", &n, &n, A, &lda, dum );
    scalea = 0;
    if (anrm > 0. && anrm < smlnum) {
        scalea = 1;
        cscale = smlnum;
    } else if (anrm > bignum) {
        scalea = 1;
        cscale = bignum;
    }
    if (scalea) {
        lapackf77_dlascl( "G", &izero, &izero, &anrm, &cscale, &n, &n, A, &lda, &ierr );
    }

    /* Balance the matrix
     * (Workspace: need N)
     *  - this space is reserved until after gebak */
    ibal = 0;
    lapackf77_dgebal( "B", &n, A, &lda, &ilo, &ihi, &work[ibal], &ierr );

    /* Reduce to upper Hessenberg form
     * (Workspace: need 3*N, prefer 2*N + N*NB)
     *  - including N reserved for gebal/gebak, unused by dgehrd */
    itau = ibal + n;
    iwrk = itau + n;
    liwrk = lwork - iwrk;

    timer_start( time_gehrd );
    flops_start( flop_gehrd );
    #if defined(Version1)
        // Version 1 - LAPACK
        lapackf77_dgehrd( &n, &ilo, &ihi, A, &lda,
                          &work[itau], &work[iwrk], &liwrk, &ierr );
    #elif defined(Version2)
        // Version 2 - LAPACK consistent HRD
        magma_dgehrd2( n, ilo, ihi, A, lda,
                       &work[itau], &work[iwrk], liwrk, &ierr );
    #elif defined(Version3)
        // Version 3 - LAPACK consistent MAGMA HRD + T matrices stored,
        magma_dgehrd( n, ilo, ihi, A, lda,
                      &work[itau], &work[iwrk], liwrk, dT, &ierr );
    #elif defined(Version4) || defined(Version5)
        // Version 4 - Multi-GPU, T on host
        magma_dgehrd_m( n, ilo, ihi, A, lda,
                        &work[itau], &work[iwrk], liwrk, T, &ierr );
        magma_dsetmatrix( nb, n, T, nb, dT, nb );
    #endif
    time_sum += timer_stop( time_gehrd );
    flop_sum += flops_stop( flop_gehrd );

    if (wantvl) {
        /* Want left eigenvectors
         * Copy Householder vectors to VL */
        side = MagmaLeft;
        lapackf77_dlacpy( MagmaLowerStr, &n, &n, A, &lda, VL, &ldvl );

        /* Generate orthogonal matrix in VL
         * (Workspace: need 3*N-1, prefer 2*N + (N-1)*NB)
         *  - including N reserved for gebal/gebak, unused by dorghr */
        timer_start( time_unghr );
        flops_start( flop_unghr );
        #if defined(Version1) || defined(Version2)
            // Version 1 & 2 - LAPACK
            lapackf77_dorghr( &n, &ilo, &ihi, VL, &ldvl, &work[itau],
                              &work[iwrk], &liwrk, &ierr );
        #elif defined(Version3) || defined(Version4)
            // Version 3 - LAPACK consistent MAGMA HRD + T matrices stored
            magma_dorghr( n, ilo, ihi, VL, ldvl, &work[itau], dT, nb, &ierr );
        #elif defined(Version5)
            // Version 5 - Multi-GPU, T on host
            magma_dorghr_m( n, ilo, ihi, VL, ldvl, &work[itau], T, nb, &ierr );
        #endif
        time_sum += timer_stop( time_unghr );
        flop_sum += flops_stop( flop_unghr );

        timer_start( time_hseqr );
        flops_start( flop_hseqr );
        /* Perform QR iteration, accumulating Schur vectors in VL
         * (Workspace: need N+1, prefer N+HSWORK (see comments) )
         *  - including N reserved for gebal/gebak, unused by dhseqr */
        iwrk = itau;
        liwrk = lwork - iwrk;
        lapackf77_dhseqr( "S", "V", &n, &ilo, &ihi, A, &lda, wr, wi,
                          VL, &ldvl, &work[iwrk], &liwrk, info );
        time_sum += timer_stop( time_hseqr );
        flop_sum += flops_stop( flop_hseqr );

        if (wantvr) {
            /* Want left and right eigenvectors
             * Copy Schur vectors to VR */
            side = MagmaBothSides;
            lapackf77_dlacpy( "F", &n, &n, VL, &ldvl, VR, &ldvr );
        }
    }
    else if (wantvr) {
        /* Want right eigenvectors
         * Copy Householder vectors to VR */
        side = MagmaRight;
        lapackf77_dlacpy( "L", &n, &n, A, &lda, VR, &ldvr );

        /* Generate orthogonal matrix in VR
         * (Workspace: need 3*N-1, prefer 2*N + (N-1)*NB)
         *  - including N reserved for gebal/gebak, unused by dorghr */
        timer_start( time_unghr );
        flops_start( flop_unghr );
        #if defined(Version1) || defined(Version2)
            // Version 1 & 2 - LAPACK
            lapackf77_dorghr( &n, &ilo, &ihi, VR, &ldvr, &work[itau],
                              &work[iwrk], &liwrk, &ierr );
        #elif defined(Version3) || defined(Version4)
            // Version 3 - LAPACK consistent MAGMA HRD + T matrices stored
            magma_dorghr( n, ilo, ihi, VR, ldvr, &work[itau], dT, nb, &ierr );
        #elif defined(Version5)
            // Version 5 - Multi-GPU, T on host
            magma_dorghr_m( n, ilo, ihi, VR, ldvr, &work[itau], T, nb, &ierr );
        #endif
        time_sum += timer_stop( time_unghr );
        flop_sum += flops_stop( flop_unghr );

        /* Perform QR iteration, accumulating Schur vectors in VR
         * (Workspace: need N+1, prefer N+HSWORK (see comments) )
         *  - including N reserved for gebal/gebak, unused by dhseqr */
        timer_start( time_hseqr );
        flops_start( flop_hseqr );
        iwrk = itau;
        liwrk = lwork - iwrk;
        lapackf77_dhseqr( "S", "V", &n, &ilo, &ihi, A, &lda, wr, wi,
                          VR, &ldvr, &work[iwrk], &liwrk, info );
        time_sum += timer_stop( time_hseqr );
        flop_sum += flops_stop( flop_hseqr );
    }
    else {
        /* Compute eigenvalues only
         * (Workspace: need N+1, prefer N+HSWORK (see comments) )
         *  - including N reserved for gebal/gebak, unused by dhseqr */
        timer_start( time_hseqr );
        flops_start( flop_hseqr );
        iwrk = itau;
        liwrk = lwork - iwrk;
        lapackf77_dhseqr( "E", "N", &n, &ilo, &ihi, A, &lda, wr, wi,
                          VR, &ldvr, &work[iwrk], &liwrk, info );
        time_sum += timer_stop( time_hseqr );
        flop_sum += flops_stop( flop_hseqr );
    }

    /* If INFO > 0 from DHSEQR, then quit */
    if (*info > 0) {
        goto CLEANUP;
    }

    timer_start( time_trevc );
    flops_start( flop_trevc );
    if (wantvl || wantvr) {
        /* Compute left and/or right eigenvectors
         * (Workspace: need 4*N, prefer (2 + 2*nb)*N)
         *  - including N reserved for gebal/gebak, unused by dtrevc */
        liwrk = lwork - iwrk;
        #if TREVC_VERSION == 1
        lapackf77_dtrevc( lapack_side_const(side), "B", select, &n, A, &lda, VL, &ldvl,
                          VR, &ldvr, &n, &nout, &work[iwrk], &ierr );
        #elif TREVC_VERSION == 2
        lapackf77_dtrevc3( lapack_side_const(side), "B", select, &n, A, &lda, VL, &ldvl,
                           VR, &ldvr, &n, &nout, &work[iwrk], &liwrk, &ierr );
        #elif TREVC_VERSION == 3
        magma_dtrevc3( side, MagmaBacktransVec, select, n, A, lda, VL, ldvl,
                       VR, ldvr, n, &nout, &work[iwrk], liwrk, &ierr );
        #elif TREVC_VERSION == 4
        magma_dtrevc3_mt( side, MagmaBacktransVec, select, n, A, lda, VL, ldvl,
                          VR, ldvr, n, &nout, &work[iwrk], liwrk, &ierr );
        #elif TREVC_VERSION == 5
        magma_dtrevc3_mt_gpu( side, MagmaBacktransVec, select, n, A, lda, VL, ldvl,
                              VR, ldvr, n, &nout, &work[iwrk], liwrk, &ierr );
        #else
        #error Unknown TREVC_VERSION
        #endif
    }
    time_sum += timer_stop( time_trevc );
    flop_sum += flops_stop( flop_trevc );

    if (wantvl) {
        /* Undo balancing of left eigenvectors
         * (Workspace: need N) */
        lapackf77_dgebak( "B", "L", &n, &ilo, &ihi, &work[ibal], &n,
                          VL, &ldvl, &ierr );

        /* Normalize left eigenvectors and make largest component real */
        for (i = 0; i < n; ++i) {
            if ( wi[i] == 0. ) {
                scl = 1. / magma_cblas_dnrm2( n, VL(0,i), 1 );
                blasf77_dscal( &n, &scl, VL(0,i), &ione );
            }
            else if ( wi[i] > 0. ) {
                d__1 = magma_cblas_dnrm2( n, VL(0,i), 1 );
                d__2 = magma_cblas_dnrm2( n, VL(0,i+1), 1 );
                scl = 1. / lapackf77_dlapy2( &d__1, &d__2 );
                blasf77_dscal( &n, &scl, VL(0,i), &ione );
                blasf77_dscal( &n, &scl, VL(0,i+1), &ione );
                for (k = 0; k < n; ++k) {
                    /* Computing 2nd power */
                    d__1 = *VL(k,i);
                    d__2 = *VL(k,i+1);
                    work[iwrk + k] = d__1*d__1 + d__2*d__2;
                }
                k = blasf77_idamax( &n, &work[iwrk], &ione ) - 1;  // subtract 1; k is 0-based
                lapackf77_dlartg( VL(k,i), VL(k,i+1), &cs, &sn, &r );
                blasf77_drot( &n, VL(0,i), &ione, VL(0,i+1), &ione, &cs, &sn );
                *VL(k,i+1) = 0.;
            }
        }
    }

    if (wantvr) {
        /* Undo balancing of right eigenvectors
         * (Workspace: need N) */
        lapackf77_dgebak( "B", "R", &n, &ilo, &ihi, &work[ibal], &n,
                          VR, &ldvr, &ierr );

        /* Normalize right eigenvectors and make largest component real */
        for (i = 0; i < n; ++i) {
            if ( wi[i] == 0. ) {
                scl = 1. / magma_cblas_dnrm2( n, VR(0,i), 1 );
                blasf77_dscal( &n, &scl, VR(0,i), &ione );
            }
            else if ( wi[i] > 0. ) {
                d__1 = magma_cblas_dnrm2( n, VR(0,i), 1 );
                d__2 = magma_cblas_dnrm2( n, VR(0,i+1), 1 );
                scl = 1. / lapackf77_dlapy2( &d__1, &d__2 );
                blasf77_dscal( &n, &scl, VR(0,i), &ione );
                blasf77_dscal( &n, &scl, VR(0,i+1), &ione );
                for (k = 0; k < n; ++k) {
                    /* Computing 2nd power */
                    d__1 = *VR(k,i);
                    d__2 = *VR(k,i+1);
                    work[iwrk + k] = d__1*d__1 + d__2*d__2;
                }
                k = blasf77_idamax( &n, &work[iwrk], &ione ) - 1;  // subtract 1; k is 0-based
                lapackf77_dlartg( VR(k,i), VR(k,i+1), &cs, &sn, &r );
                blasf77_drot( &n, VR(0,i), &ione, VR(0,i+1), &ione, &cs, &sn );
                *VR(k,i+1) = 0.;
            }
        }
    }

CLEANUP:
    /* Undo scaling if necessary */
    if (scalea) {
        // converged eigenvalues, stored in wr[i+1:n] and wi[i+1:n] for i = INFO
        magma_int_t nval = n - (*info);
        magma_int_t ld = max( nval, 1 );
        lapackf77_dlascl( "G", &izero, &izero, &cscale, &anrm, &nval, &ione, wr + (*info), &ld, &ierr );
        lapackf77_dlascl( "G", &izero, &izero, &cscale, &anrm, &nval, &ione, wi + (*info), &ld, &ierr );
        if (*info > 0) {
            // first ilo columns were already upper triangular,
            // so the corresponding eigenvalues are also valid.
            nval = ilo - 1;
            lapackf77_dlascl( "G", &izero, &izero, &cscale, &anrm, &nval, &ione, wr, &n, &ierr );
            lapackf77_dlascl( "G", &izero, &izero, &cscale, &anrm, &nval, &ione, wi, &n, &ierr );
        }
    }

    #if defined(Version3) || defined(Version4) || defined(Version5)
    magma_free( dT );
    #endif
    #if defined(Version4) || defined(Version5)
    magma_free_cpu( T );
    #endif
    
    timer_stop( time_total );
    flops_stop( flop_total );
    timer_printf( "dgeev times n %5d, gehrd %7.3f, unghr %7.3f, hseqr %7.3f, trevc %7.3f, total %7.3f, sum %7.3f\n",
                  (int) n, time_gehrd, time_unghr, time_hseqr, time_trevc, time_total, time_sum );
    timer_printf( "dgeev flops n %5d, gehrd %7lld, unghr %7lld, hseqr %7lld, trevc %7lld, total %7lld, sum %7lld\n",
                  (int) n, flop_gehrd, flop_unghr, flop_hseqr, flop_trevc, flop_total, flop_sum );
    
    work[0] = MAGMA_D_MAKE( (double) optwrk, 0. );
    
    return *info;
} /* magma_dgeev */