src/gromacs/linearalgebra/gmx_lapack/dlasd3.c

   1 #include <math.h>
   2 #include "../gmx_blas.h"
   3 #include "../gmx_lapack.h"
   4
   5 void
   6 F77_FUNC(dlasd3,DLASD3)(int *nl,
   7         int *nr,
   8         int *sqre,
   9         int *k,
  10         double *d__,
  11         double *q,
  12         int *ldq,
  13         double *dsigma,
  14         double *u,
  15         int *ldu,
  16         double *u2,
  17         int *ldu2,
  18         double *vt,
  19         int *ldvt,
  20         double *vt2,
  21         int *ldvt2,
  22         int *idxc,
  23         int *ctot,
  24         double *z__,
  25         int *info)
  26 {
  27     int q_dim1, q_offset, u_dim1, u_offset, u2_dim1, u2_offset, vt_dim1,
  28             vt_offset, vt2_dim1, vt2_offset, i__1, i__2;
  29     double d__2;
  30
  31     int i__, j, m, n, jc;
  32     double rho;
  33     int nlp1, nlp2, nrp1;
  34     double temp;
  35     int ctemp;
  36     int ktemp;
  37     int c__1 = 1;
  38     int c__0 = 0;
  39     double zero = 0.0;
  40     double one = 1.0;
  41     double *p1,*p2,t1,t2;
  42
  43     p1 = &t1;
  44     p2 = &t2;
  45
  46     --d__;
  47     q_dim1 = *ldq;
  48     q_offset = 1 + q_dim1;
  49     q -= q_offset;
  50     --dsigma;
  51     u_dim1 = *ldu;
  52     u_offset = 1 + u_dim1;
  53     u -= u_offset;
  54     u2_dim1 = *ldu2;
  55     u2_offset = 1 + u2_dim1;
  56     u2 -= u2_offset;
  57     vt_dim1 = *ldvt;
  58     vt_offset = 1 + vt_dim1;
  59     vt -= vt_offset;
  60     vt2_dim1 = *ldvt2;
  61     vt2_offset = 1 + vt2_dim1;
  62     vt2 -= vt2_offset;
  63     --idxc;
  64     --ctot;
  65     --z__;
  66
  67     /* Function Body */
  68     *info = 0;
  69
  70     if (*nl < 1) {
  71         *info = -1;
  72     } else if (*nr < 1) {
  73         *info = -2;
  74     } else if (*sqre != 1 && *sqre != 0) {
  75         *info = -3;
  76     }
  77
  78     n = *nl + *nr + 1;
  79     m = n + *sqre;
  80     nlp1 = *nl + 1;
  81     nlp2 = *nl + 2;
  82
  83     if (*k == 1) {
  84         d__[1] = fabs(z__[1]);
  85         F77_FUNC(dcopy,DCOPY)(&m, &vt2[vt2_dim1 + 1], ldvt2, &vt[vt_dim1 + 1], ldvt);
  86         if (z__[1] > 0.) {
  87             F77_FUNC(dcopy,DCOPY)(&n, &u2[u2_dim1 + 1], &c__1, &u[u_dim1 + 1], &c__1);
  88         } else {
  89             i__1 = n;
  90             for (i__ = 1; i__ <= i__1; ++i__) {
  91                 u[i__ + u_dim1] = -u2[i__ + u2_dim1];
  92             }
  93         }
  94         return;
  95     }
  96
  97     i__1 = *k;
  98     for (i__ = 1; i__ <= i__1; ++i__) {
  99       t1 = dsigma[i__];
 100       t2 = dsigma[i__];
 101       /* force store and reload from memory */
 102       t1 = (*p1) + (*p2) - dsigma[i__];
 103
 104       dsigma[i__] = t1;
 105     }
 106
 107     F77_FUNC(dcopy,DCOPY)(k, &z__[1], &c__1, &q[q_offset], &c__1);
 108
 109     rho = F77_FUNC(dnrm2,DNRM2)(k, &z__[1], &c__1);
 110     F77_FUNC(dlascl,DLASCL)("G", &c__0, &c__0, &rho, &one, k, &c__1, &z__[1], k, info);
 111     rho *= rho;
 112
 113
 114     i__1 = *k;
 115     for (j = 1; j <= i__1; ++j) {
 116         F77_FUNC(dlasd4,DLASD4)(k, &j, &dsigma[1], &z__[1], &u[j * u_dim1 + 1], &rho, &d__[j],
 117                  &vt[j * vt_dim1 + 1], info);
 118
 119         if (*info != 0) {
 120             return;
 121         }
 122     }
 123
 124     i__1 = *k;
 125     for (i__ = 1; i__ <= i__1; ++i__) {
 126         z__[i__] = u[i__ + *k * u_dim1] * vt[i__ + *k * vt_dim1];
 127         i__2 = i__ - 1;
 128         for (j = 1; j <= i__2; ++j) {
 129             z__[i__] *= u[i__ + j * u_dim1] * vt[i__ + j * vt_dim1] / (dsigma[
 130                     i__] - dsigma[j]) / (dsigma[i__] + dsigma[j]);
 131         }
 132         i__2 = *k - 1;
 133         for (j = i__; j <= i__2; ++j) {
 134             z__[i__] *= u[i__ + j * u_dim1] * vt[i__ + j * vt_dim1] / (dsigma[
 135                     i__] - dsigma[j + 1]) / (dsigma[i__] + dsigma[j + 1]);
 136         }
 137         d__2 = sqrt(fabs(z__[i__]));
 138         z__[i__] = (q[i__ + q_dim1] > 0) ? d__2 : -d__2;
 139     }
 140
 141     i__1 = *k;
 142     for (i__ = 1; i__ <= i__1; ++i__) {
 143         vt[i__ * vt_dim1 + 1] = z__[1] / u[i__ * u_dim1 + 1] / vt[i__ *
 144                 vt_dim1 + 1];
 145         u[i__ * u_dim1 + 1] = -1.;
 146         i__2 = *k;
 147         for (j = 2; j <= i__2; ++j) {
 148             vt[j + i__ * vt_dim1] = z__[j] / u[j + i__ * u_dim1] / vt[j + i__
 149                     * vt_dim1];
 150             u[j + i__ * u_dim1] = dsigma[j] * vt[j + i__ * vt_dim1];
 151         }
 152         temp = F77_FUNC(dnrm2,DNRM2)(k, &u[i__ * u_dim1 + 1], &c__1);
 153         q[i__ * q_dim1 + 1] = u[i__ * u_dim1 + 1] / temp;
 154         i__2 = *k;
 155         for (j = 2; j <= i__2; ++j) {
 156             jc = idxc[j];
 157             q[j + i__ * q_dim1] = u[jc + i__ * u_dim1] / temp;
 158         }
 159     }
 160
 161     if (*k == 2) {
 162         F77_FUNC(dgemm,DGEMM)("N", "N", &n, k, k, &one, &u2[u2_offset], ldu2, &q[q_offset],
 163                  ldq, &zero, &u[u_offset], ldu);
 164         goto L100;
 165     }
 166     if (ctot[1] > 0) {
 167         F77_FUNC(dgemm,DGEMM)("N", "N", nl, k, &ctot[1], &one, &u2[(u2_dim1 << 1) + 1],
 168                 ldu2, &q[q_dim1 + 2], ldq, &zero, &u[u_dim1 + 1], ldu);
 169         if (ctot[3] > 0) {
 170             ktemp = ctot[1] + 2 + ctot[2];
 171             F77_FUNC(dgemm,DGEMM)("N", "N", nl, k, &ctot[3], &one, &u2[ktemp * u2_dim1 + 1]
 172                     , ldu2, &q[ktemp + q_dim1], ldq, &one, &u[u_dim1 + 1],
 173                     ldu);
 174         }
 175     } else if (ctot[3] > 0) {
 176         ktemp = ctot[1] + 2 + ctot[2];
 177         F77_FUNC(dgemm,DGEMM)("N", "N", nl, k, &ctot[3], &one, &u2[ktemp * u2_dim1 + 1],
 178                 ldu2, &q[ktemp + q_dim1], ldq, &zero, &u[u_dim1 + 1], ldu);
 179     } else {
 180         F77_FUNC(dlacpy,DLACPY)("F", nl, k, &u2[u2_offset], ldu2, &u[u_offset], ldu);
 181     }
 182     F77_FUNC(dcopy,DCOPY)(k, &q[q_dim1 + 1], ldq, &u[nlp1 + u_dim1], ldu);
 183     ktemp = ctot[1] + 2;
 184     ctemp = ctot[2] + ctot[3];
 185     F77_FUNC(dgemm,DGEMM)("N", "N", nr, k, &ctemp, &one, &u2[nlp2 + ktemp * u2_dim1], ldu2,
 186              &q[ktemp + q_dim1], ldq, &zero, &u[nlp2 + u_dim1], ldu);
 187
 188 L100:
 189     i__1 = *k;
 190     for (i__ = 1; i__ <= i__1; ++i__) {
 191         temp = F77_FUNC(dnrm2,DNRM2)(k, &vt[i__ * vt_dim1 + 1], &c__1);
 192         q[i__ + q_dim1] = vt[i__ * vt_dim1 + 1] / temp;
 193         i__2 = *k;
 194         for (j = 2; j <= i__2; ++j) {
 195             jc = idxc[j];
 196             q[i__ + j * q_dim1] = vt[jc + i__ * vt_dim1] / temp;
 197         }
 198     }
 199
 200     if (*k == 2) {
 201         F77_FUNC(dgemm,DGEMM)("N", "N", k, &m, k, &one, &q[q_offset], ldq, &vt2[vt2_offset]
 202                 , ldvt2, &zero, &vt[vt_offset], ldvt);
 203         return;
 204     }
 205     ktemp = ctot[1] + 1;
 206     F77_FUNC(dgemm,DGEMM)("N", "N", k, &nlp1, &ktemp, &one, &q[q_dim1 + 1], ldq, &vt2[
 207             vt2_dim1 + 1], ldvt2, &zero, &vt[vt_dim1 + 1], ldvt);
 208     ktemp = ctot[1] + 2 + ctot[2];
 209     if (ktemp <= *ldvt2) {
 210         F77_FUNC(dgemm,DGEMM)("N", "N", k, &nlp1, &ctot[3], &one, &q[ktemp * q_dim1 + 1],
 211                 ldq, &vt2[ktemp + vt2_dim1], ldvt2, &one, &vt[vt_dim1 + 1],
 212                 ldvt);
 213     }
 214
 215     ktemp = ctot[1] + 1;
 216     nrp1 = *nr + *sqre;
 217     if (ktemp > 1) {
 218         i__1 = *k;
 219         for (i__ = 1; i__ <= i__1; ++i__) {
 220             q[i__ + ktemp * q_dim1] = q[i__ + q_dim1];
 221         }
 222         i__1 = m;
 223         for (i__ = nlp2; i__ <= i__1; ++i__) {
 224             vt2[ktemp + i__ * vt2_dim1] = vt2[i__ * vt2_dim1 + 1];
 225         }
 226     }
 227     ctemp = ctot[2] + 1 + ctot[3];
 228     F77_FUNC(dgemm,DGEMM)("N", "N", k, &nrp1, &ctemp, &one, &q[ktemp * q_dim1 + 1], ldq, &
 229             vt2[ktemp + nlp2 * vt2_dim1], ldvt2, &zero, &vt[nlp2 * vt_dim1 +
 230             1], ldvt);
 231
 232     return;
 233
 234
 235 }
 236
 237