158 lines
6.4 KiB
C++
158 lines
6.4 KiB
C++
#ifdef __cplusplus
|
|
extern "C" {
|
|
#endif
|
|
#include "lmp_f2c.h"
|
|
static doublereal c_b6 = -1.;
|
|
static integer c__1 = 1;
|
|
static doublereal c_b27 = 1.;
|
|
int dsygs2_(integer *itype, char *uplo, integer *n, doublereal *a, integer *lda, doublereal *b,
|
|
integer *ldb, integer *info, ftnlen uplo_len)
|
|
{
|
|
integer a_dim1, a_offset, b_dim1, b_offset, i__1, i__2;
|
|
doublereal d__1;
|
|
integer k;
|
|
doublereal ct, akk, bkk;
|
|
extern int dsyr2_(char *, integer *, doublereal *, doublereal *, integer *, doublereal *,
|
|
integer *, doublereal *, integer *, ftnlen),
|
|
dscal_(integer *, doublereal *, doublereal *, integer *);
|
|
extern logical lsame_(char *, char *, ftnlen, ftnlen);
|
|
extern int daxpy_(integer *, doublereal *, doublereal *, integer *, doublereal *, integer *);
|
|
logical upper;
|
|
extern int dtrmv_(char *, char *, char *, integer *, doublereal *, integer *, doublereal *,
|
|
integer *, ftnlen, ftnlen, ftnlen),
|
|
dtrsv_(char *, char *, char *, integer *, doublereal *, integer *, doublereal *, integer *,
|
|
ftnlen, ftnlen, ftnlen),
|
|
xerbla_(char *, integer *, ftnlen);
|
|
a_dim1 = *lda;
|
|
a_offset = 1 + a_dim1;
|
|
a -= a_offset;
|
|
b_dim1 = *ldb;
|
|
b_offset = 1 + b_dim1;
|
|
b -= b_offset;
|
|
*info = 0;
|
|
upper = lsame_(uplo, (char *)"U", (ftnlen)1, (ftnlen)1);
|
|
if (*itype < 1 || *itype > 3) {
|
|
*info = -1;
|
|
} else if (!upper && !lsame_(uplo, (char *)"L", (ftnlen)1, (ftnlen)1)) {
|
|
*info = -2;
|
|
} else if (*n < 0) {
|
|
*info = -3;
|
|
} else if (*lda < max(1, *n)) {
|
|
*info = -5;
|
|
} else if (*ldb < max(1, *n)) {
|
|
*info = -7;
|
|
}
|
|
if (*info != 0) {
|
|
i__1 = -(*info);
|
|
xerbla_((char *)"DSYGS2", &i__1, (ftnlen)6);
|
|
return 0;
|
|
}
|
|
if (*itype == 1) {
|
|
if (upper) {
|
|
i__1 = *n;
|
|
for (k = 1; k <= i__1; ++k) {
|
|
akk = a[k + k * a_dim1];
|
|
bkk = b[k + k * b_dim1];
|
|
d__1 = bkk;
|
|
akk /= d__1 * d__1;
|
|
a[k + k * a_dim1] = akk;
|
|
if (k < *n) {
|
|
i__2 = *n - k;
|
|
d__1 = 1. / bkk;
|
|
dscal_(&i__2, &d__1, &a[k + (k + 1) * a_dim1], lda);
|
|
ct = akk * -.5;
|
|
i__2 = *n - k;
|
|
daxpy_(&i__2, &ct, &b[k + (k + 1) * b_dim1], ldb, &a[k + (k + 1) * a_dim1],
|
|
lda);
|
|
i__2 = *n - k;
|
|
dsyr2_(uplo, &i__2, &c_b6, &a[k + (k + 1) * a_dim1], lda,
|
|
&b[k + (k + 1) * b_dim1], ldb, &a[k + 1 + (k + 1) * a_dim1], lda,
|
|
(ftnlen)1);
|
|
i__2 = *n - k;
|
|
daxpy_(&i__2, &ct, &b[k + (k + 1) * b_dim1], ldb, &a[k + (k + 1) * a_dim1],
|
|
lda);
|
|
i__2 = *n - k;
|
|
dtrsv_(uplo, (char *)"T", (char *)"N", &i__2, &b[k + 1 + (k + 1) * b_dim1], ldb,
|
|
&a[k + (k + 1) * a_dim1], lda, (ftnlen)1, (ftnlen)1, (ftnlen)1);
|
|
}
|
|
}
|
|
} else {
|
|
i__1 = *n;
|
|
for (k = 1; k <= i__1; ++k) {
|
|
akk = a[k + k * a_dim1];
|
|
bkk = b[k + k * b_dim1];
|
|
d__1 = bkk;
|
|
akk /= d__1 * d__1;
|
|
a[k + k * a_dim1] = akk;
|
|
if (k < *n) {
|
|
i__2 = *n - k;
|
|
d__1 = 1. / bkk;
|
|
dscal_(&i__2, &d__1, &a[k + 1 + k * a_dim1], &c__1);
|
|
ct = akk * -.5;
|
|
i__2 = *n - k;
|
|
daxpy_(&i__2, &ct, &b[k + 1 + k * b_dim1], &c__1, &a[k + 1 + k * a_dim1],
|
|
&c__1);
|
|
i__2 = *n - k;
|
|
dsyr2_(uplo, &i__2, &c_b6, &a[k + 1 + k * a_dim1], &c__1,
|
|
&b[k + 1 + k * b_dim1], &c__1, &a[k + 1 + (k + 1) * a_dim1], lda,
|
|
(ftnlen)1);
|
|
i__2 = *n - k;
|
|
daxpy_(&i__2, &ct, &b[k + 1 + k * b_dim1], &c__1, &a[k + 1 + k * a_dim1],
|
|
&c__1);
|
|
i__2 = *n - k;
|
|
dtrsv_(uplo, (char *)"N", (char *)"N", &i__2, &b[k + 1 + (k + 1) * b_dim1], ldb,
|
|
&a[k + 1 + k * a_dim1], &c__1, (ftnlen)1, (ftnlen)1, (ftnlen)1);
|
|
}
|
|
}
|
|
}
|
|
} else {
|
|
if (upper) {
|
|
i__1 = *n;
|
|
for (k = 1; k <= i__1; ++k) {
|
|
akk = a[k + k * a_dim1];
|
|
bkk = b[k + k * b_dim1];
|
|
i__2 = k - 1;
|
|
dtrmv_(uplo, (char *)"N", (char *)"N", &i__2, &b[b_offset], ldb, &a[k * a_dim1 + 1], &c__1,
|
|
(ftnlen)1, (ftnlen)1, (ftnlen)1);
|
|
ct = akk * .5;
|
|
i__2 = k - 1;
|
|
daxpy_(&i__2, &ct, &b[k * b_dim1 + 1], &c__1, &a[k * a_dim1 + 1], &c__1);
|
|
i__2 = k - 1;
|
|
dsyr2_(uplo, &i__2, &c_b27, &a[k * a_dim1 + 1], &c__1, &b[k * b_dim1 + 1], &c__1,
|
|
&a[a_offset], lda, (ftnlen)1);
|
|
i__2 = k - 1;
|
|
daxpy_(&i__2, &ct, &b[k * b_dim1 + 1], &c__1, &a[k * a_dim1 + 1], &c__1);
|
|
i__2 = k - 1;
|
|
dscal_(&i__2, &bkk, &a[k * a_dim1 + 1], &c__1);
|
|
d__1 = bkk;
|
|
a[k + k * a_dim1] = akk * (d__1 * d__1);
|
|
}
|
|
} else {
|
|
i__1 = *n;
|
|
for (k = 1; k <= i__1; ++k) {
|
|
akk = a[k + k * a_dim1];
|
|
bkk = b[k + k * b_dim1];
|
|
i__2 = k - 1;
|
|
dtrmv_(uplo, (char *)"T", (char *)"N", &i__2, &b[b_offset], ldb, &a[k + a_dim1], lda, (ftnlen)1,
|
|
(ftnlen)1, (ftnlen)1);
|
|
ct = akk * .5;
|
|
i__2 = k - 1;
|
|
daxpy_(&i__2, &ct, &b[k + b_dim1], ldb, &a[k + a_dim1], lda);
|
|
i__2 = k - 1;
|
|
dsyr2_(uplo, &i__2, &c_b27, &a[k + a_dim1], lda, &b[k + b_dim1], ldb, &a[a_offset],
|
|
lda, (ftnlen)1);
|
|
i__2 = k - 1;
|
|
daxpy_(&i__2, &ct, &b[k + b_dim1], ldb, &a[k + a_dim1], lda);
|
|
i__2 = k - 1;
|
|
dscal_(&i__2, &bkk, &a[k + a_dim1], lda);
|
|
d__1 = bkk;
|
|
a[k + k * a_dim1] = akk * (d__1 * d__1);
|
|
}
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
#ifdef __cplusplus
|
|
}
|
|
#endif
|