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lammps-gran-kokkos/lib/linalg/dlasd1.cpp
2024-11-09 04:14:11 -05:00

97 lines
3.4 KiB
C++

#ifdef __cplusplus
extern "C" {
#endif
#include "lmp_f2c.h"
static integer c__0 = 0;
static doublereal c_b7 = 1.;
static integer c__1 = 1;
static integer c_n1 = -1;
int dlasd1_(integer *nl, integer *nr, integer *sqre, doublereal *d__, doublereal *alpha,
doublereal *beta, doublereal *u, integer *ldu, doublereal *vt, integer *ldvt,
integer *idxq, integer *iwork, doublereal *work, integer *info)
{
integer u_dim1, u_offset, vt_dim1, vt_offset, i__1;
doublereal d__1, d__2;
integer i__, k, m, n, n1, n2, iq, iz, iu2, ldq, idx, ldu2, ivt2, idxc, idxp, ldvt2;
extern int dlasd2_(integer *, integer *, integer *, integer *, doublereal *, doublereal *,
doublereal *, doublereal *, doublereal *, integer *, doublereal *, integer *,
doublereal *, doublereal *, integer *, doublereal *, integer *, integer *,
integer *, integer *, integer *, integer *, integer *),
dlasd3_(integer *, integer *, integer *, integer *, doublereal *, doublereal *, integer *,
doublereal *, doublereal *, integer *, doublereal *, integer *, doublereal *,
integer *, doublereal *, integer *, integer *, integer *, doublereal *, integer *),
dlascl_(char *, integer *, integer *, doublereal *, doublereal *, integer *, integer *,
doublereal *, integer *, integer *, ftnlen),
dlamrg_(integer *, integer *, doublereal *, integer *, integer *, integer *);
integer isigma;
extern int xerbla_(char *, integer *, ftnlen);
doublereal orgnrm;
integer coltyp;
--d__;
u_dim1 = *ldu;
u_offset = 1 + u_dim1;
u -= u_offset;
vt_dim1 = *ldvt;
vt_offset = 1 + vt_dim1;
vt -= vt_offset;
--idxq;
--iwork;
--work;
*info = 0;
if (*nl < 1) {
*info = -1;
} else if (*nr < 1) {
*info = -2;
} else if (*sqre < 0 || *sqre > 1) {
*info = -3;
}
if (*info != 0) {
i__1 = -(*info);
xerbla_((char *)"DLASD1", &i__1, (ftnlen)6);
return 0;
}
n = *nl + *nr + 1;
m = n + *sqre;
ldu2 = n;
ldvt2 = m;
iz = 1;
isigma = iz + m;
iu2 = isigma + n;
ivt2 = iu2 + ldu2 * n;
iq = ivt2 + ldvt2 * m;
idx = 1;
idxc = idx + n;
coltyp = idxc + n;
idxp = coltyp + n;
d__1 = abs(*alpha), d__2 = abs(*beta);
orgnrm = max(d__1, d__2);
d__[*nl + 1] = 0.;
i__1 = n;
for (i__ = 1; i__ <= i__1; ++i__) {
if ((d__1 = d__[i__], abs(d__1)) > orgnrm) {
orgnrm = (d__1 = d__[i__], abs(d__1));
}
}
dlascl_((char *)"G", &c__0, &c__0, &orgnrm, &c_b7, &n, &c__1, &d__[1], &n, info, (ftnlen)1);
*alpha /= orgnrm;
*beta /= orgnrm;
dlasd2_(nl, nr, sqre, &k, &d__[1], &work[iz], alpha, beta, &u[u_offset], ldu, &vt[vt_offset],
ldvt, &work[isigma], &work[iu2], &ldu2, &work[ivt2], &ldvt2, &iwork[idxp], &iwork[idx],
&iwork[idxc], &idxq[1], &iwork[coltyp], info);
ldq = k;
dlasd3_(nl, nr, sqre, &k, &d__[1], &work[iq], &ldq, &work[isigma], &u[u_offset], ldu,
&work[iu2], &ldu2, &vt[vt_offset], ldvt, &work[ivt2], &ldvt2, &iwork[idxc],
&iwork[coltyp], &work[iz], info);
if (*info != 0) {
return 0;
}
dlascl_((char *)"G", &c__0, &c__0, &c_b7, &orgnrm, &n, &c__1, &d__[1], &n, info, (ftnlen)1);
n1 = k;
n2 = n - k;
dlamrg_(&n1, &n2, &d__[1], &c__1, &c_n1, &idxq[1]);
return 0;
}
#ifdef __cplusplus
}
#endif