slasd0.c

最著名最快的分子模拟软件

#include "gmx_lapack.h"

void 
F77_FUNC(slasd0,SLASD0)(int *n, 
	int *sqre, 
	float *d__, 
	float *e, 
	float *u, 
	int *ldu, 
	float *vt, 
	int *ldvt,
	int *smlsiz, 
	int *iwork,
	float *work, 
	int *info)
{
    int u_dim1, u_offset, vt_dim1, vt_offset, i__1, i__2;

    int i__, j, m, i1, ic, lf, nd, ll, nl, nr, im1, ncc, nlf, nrf, 
	    iwk, lvl, ndb1, nlp1, nrp1;
    float beta;
    int idxq, nlvl;
    float alpha;
    int inode, ndiml, idxqc, ndimr, itemp, sqrei;
    int c__0 = 0;


    --d__;
    --e;
    u_dim1 = *ldu;
    u_offset = 1 + u_dim1;
    u -= u_offset;
    vt_dim1 = *ldvt;
    vt_offset = 1 + vt_dim1;
    vt -= vt_offset;
    --iwork;
    --work;

    *info = 0;

    if (*n < 0) {
	*info = -1;
    } else if (*sqre < 0 || *sqre > 1) {
	*info = -2;
    }

    m = *n + *sqre;

    if (*ldu < *n) {
	*info = -6;
    } else if (*ldvt < m) {
	*info = -8;
    } else if (*smlsiz < 3) {
	*info = -9;
    }
    if (*info != 0) {
	i__1 = -(*info);
	return;
    }

    if (*n <= *smlsiz) {
	F77_FUNC(slasdq,SLASDQ)("U", sqre, n, &m, n, &c__0, &d__[1], &e[1], &vt[vt_offset], 
		ldvt, &u[u_offset], ldu, &u[u_offset], ldu, &work[1], info);
	return;
    }

    inode = 1;
    ndiml = inode + *n;
    ndimr = ndiml + *n;
    idxq = ndimr + *n;
    iwk = idxq + *n;
    F77_FUNC(slasdt,SLASDT)(n, &nlvl, &nd, &iwork[inode], &iwork[ndiml], &iwork[ndimr], 
	    smlsiz);

    ndb1 = (nd + 1) / 2;
    ncc = 0;
    i__1 = nd;
    for (i__ = ndb1; i__ <= i__1; ++i__) {

	i1 = i__ - 1;
	ic = iwork[inode + i1];
	nl = iwork[ndiml + i1];
	nlp1 = nl + 1;
	nr = iwork[ndimr + i1];
	nrp1 = nr + 1;
	nlf = ic - nl;
	nrf = ic + 1;
	sqrei = 1;
	F77_FUNC(slasdq,SLASDQ)("U", &sqrei, &nl, &nlp1, &nl, &ncc, &d__[nlf], &e[nlf], &vt[
		nlf + nlf * vt_dim1], ldvt, &u[nlf + nlf * u_dim1], ldu, &u[
		nlf + nlf * u_dim1], ldu, &work[1], info);
	if (*info != 0) {
	    return;
	}
	itemp = idxq + nlf - 2;
	i__2 = nl;
	for (j = 1; j <= i__2; ++j) {
	    iwork[itemp + j] = j;
	}
	if (i__ == nd) {
	    sqrei = *sqre;
	} else {
	    sqrei = 1;
	}
	nrp1 = nr + sqrei;
	F77_FUNC(slasdq,SLASDQ)("U", &sqrei, &nr, &nrp1, &nr, &ncc, &d__[nrf], &e[nrf], &vt[
		nrf + nrf * vt_dim1], ldvt, &u[nrf + nrf * u_dim1], ldu, &u[
		nrf + nrf * u_dim1], ldu, &work[1], info);
	if (*info != 0) {
	    return;
	}
	itemp = idxq + ic;
	i__2 = nr;
	for (j = 1; j <= i__2; ++j) {
	    iwork[itemp + j - 1] = j;
	}
    }

    for (lvl = nlvl; lvl >= 1; --lvl) {

	if (lvl == 1) {
	    lf = 1;
	    ll = 1;
	} else {
	    i__1 = lvl - 1;
	    lf = (1 << i__1);
	    ll = (lf << 1) - 1;
	}
	i__1 = ll;
	for (i__ = lf; i__ <= i__1; ++i__) {
	    im1 = i__ - 1;
	    ic = iwork[inode + im1];
	    nl = iwork[ndiml + im1];
	    nr = iwork[ndimr + im1];
	    nlf = ic - nl;
	    if (*sqre == 0 && i__ == ll) {
		sqrei = *sqre;
	    } else {
		sqrei = 1;
	    }
	    idxqc = idxq + nlf - 1;
	    alpha = d__[ic];
	    beta = e[ic];
	    F77_FUNC(slasd1,SLASD1)(&nl, &nr, &sqrei, &d__[nlf], &alpha, &beta, &u[nlf + nlf *
		     u_dim1], ldu, &vt[nlf + nlf * vt_dim1], ldvt, &iwork[
		    idxqc], &iwork[iwk], &work[1], info);
	    if (*info != 0) {
		return;
	    }
	}
    }

    return;

}