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

215 lines
7.3 KiB
C++

#ifdef __cplusplus
extern "C" {
#endif
#include "lmp_f2c.h"
static doublereal c_b7 = -1.;
static integer c__1 = 1;
static doublereal c_b19 = 1.;
int dsytrs_(char *uplo, integer *n, integer *nrhs, doublereal *a, integer *lda, integer *ipiv,
doublereal *b, integer *ldb, integer *info, ftnlen uplo_len)
{
integer a_dim1, a_offset, b_dim1, b_offset, i__1;
doublereal d__1;
integer j, k;
doublereal ak, bk;
integer kp;
doublereal akm1, bkm1;
extern int dger_(integer *, integer *, doublereal *, doublereal *, integer *, doublereal *,
integer *, doublereal *, integer *);
doublereal akm1k;
extern int dscal_(integer *, doublereal *, doublereal *, integer *);
extern logical lsame_(char *, char *, ftnlen, ftnlen);
doublereal denom;
extern int dgemv_(char *, integer *, integer *, doublereal *, doublereal *, integer *,
doublereal *, integer *, doublereal *, doublereal *, integer *, ftnlen),
dswap_(integer *, doublereal *, integer *, doublereal *, integer *);
logical upper;
extern int xerbla_(char *, integer *, ftnlen);
a_dim1 = *lda;
a_offset = 1 + a_dim1;
a -= a_offset;
--ipiv;
b_dim1 = *ldb;
b_offset = 1 + b_dim1;
b -= b_offset;
*info = 0;
upper = lsame_(uplo, (char *)"U", (ftnlen)1, (ftnlen)1);
if (!upper && !lsame_(uplo, (char *)"L", (ftnlen)1, (ftnlen)1)) {
*info = -1;
} else if (*n < 0) {
*info = -2;
} else if (*nrhs < 0) {
*info = -3;
} else if (*lda < max(1, *n)) {
*info = -5;
} else if (*ldb < max(1, *n)) {
*info = -8;
}
if (*info != 0) {
i__1 = -(*info);
xerbla_((char *)"DSYTRS", &i__1, (ftnlen)6);
return 0;
}
if (*n == 0 || *nrhs == 0) {
return 0;
}
if (upper) {
k = *n;
L10:
if (k < 1) {
goto L30;
}
if (ipiv[k] > 0) {
kp = ipiv[k];
if (kp != k) {
dswap_(nrhs, &b[k + b_dim1], ldb, &b[kp + b_dim1], ldb);
}
i__1 = k - 1;
dger_(&i__1, nrhs, &c_b7, &a[k * a_dim1 + 1], &c__1, &b[k + b_dim1], ldb,
&b[b_dim1 + 1], ldb);
d__1 = 1. / a[k + k * a_dim1];
dscal_(nrhs, &d__1, &b[k + b_dim1], ldb);
--k;
} else {
kp = -ipiv[k];
if (kp != k - 1) {
dswap_(nrhs, &b[k - 1 + b_dim1], ldb, &b[kp + b_dim1], ldb);
}
i__1 = k - 2;
dger_(&i__1, nrhs, &c_b7, &a[k * a_dim1 + 1], &c__1, &b[k + b_dim1], ldb,
&b[b_dim1 + 1], ldb);
i__1 = k - 2;
dger_(&i__1, nrhs, &c_b7, &a[(k - 1) * a_dim1 + 1], &c__1, &b[k - 1 + b_dim1], ldb,
&b[b_dim1 + 1], ldb);
akm1k = a[k - 1 + k * a_dim1];
akm1 = a[k - 1 + (k - 1) * a_dim1] / akm1k;
ak = a[k + k * a_dim1] / akm1k;
denom = akm1 * ak - 1.;
i__1 = *nrhs;
for (j = 1; j <= i__1; ++j) {
bkm1 = b[k - 1 + j * b_dim1] / akm1k;
bk = b[k + j * b_dim1] / akm1k;
b[k - 1 + j * b_dim1] = (ak * bkm1 - bk) / denom;
b[k + j * b_dim1] = (akm1 * bk - bkm1) / denom;
}
k += -2;
}
goto L10;
L30:
k = 1;
L40:
if (k > *n) {
goto L50;
}
if (ipiv[k] > 0) {
i__1 = k - 1;
dgemv_((char *)"Transpose", &i__1, nrhs, &c_b7, &b[b_offset], ldb, &a[k * a_dim1 + 1], &c__1,
&c_b19, &b[k + b_dim1], ldb, (ftnlen)9);
kp = ipiv[k];
if (kp != k) {
dswap_(nrhs, &b[k + b_dim1], ldb, &b[kp + b_dim1], ldb);
}
++k;
} else {
i__1 = k - 1;
dgemv_((char *)"Transpose", &i__1, nrhs, &c_b7, &b[b_offset], ldb, &a[k * a_dim1 + 1], &c__1,
&c_b19, &b[k + b_dim1], ldb, (ftnlen)9);
i__1 = k - 1;
dgemv_((char *)"Transpose", &i__1, nrhs, &c_b7, &b[b_offset], ldb, &a[(k + 1) * a_dim1 + 1],
&c__1, &c_b19, &b[k + 1 + b_dim1], ldb, (ftnlen)9);
kp = -ipiv[k];
if (kp != k) {
dswap_(nrhs, &b[k + b_dim1], ldb, &b[kp + b_dim1], ldb);
}
k += 2;
}
goto L40;
L50:;
} else {
k = 1;
L60:
if (k > *n) {
goto L80;
}
if (ipiv[k] > 0) {
kp = ipiv[k];
if (kp != k) {
dswap_(nrhs, &b[k + b_dim1], ldb, &b[kp + b_dim1], ldb);
}
if (k < *n) {
i__1 = *n - k;
dger_(&i__1, nrhs, &c_b7, &a[k + 1 + k * a_dim1], &c__1, &b[k + b_dim1], ldb,
&b[k + 1 + b_dim1], ldb);
}
d__1 = 1. / a[k + k * a_dim1];
dscal_(nrhs, &d__1, &b[k + b_dim1], ldb);
++k;
} else {
kp = -ipiv[k];
if (kp != k + 1) {
dswap_(nrhs, &b[k + 1 + b_dim1], ldb, &b[kp + b_dim1], ldb);
}
if (k < *n - 1) {
i__1 = *n - k - 1;
dger_(&i__1, nrhs, &c_b7, &a[k + 2 + k * a_dim1], &c__1, &b[k + b_dim1], ldb,
&b[k + 2 + b_dim1], ldb);
i__1 = *n - k - 1;
dger_(&i__1, nrhs, &c_b7, &a[k + 2 + (k + 1) * a_dim1], &c__1, &b[k + 1 + b_dim1],
ldb, &b[k + 2 + b_dim1], ldb);
}
akm1k = a[k + 1 + k * a_dim1];
akm1 = a[k + k * a_dim1] / akm1k;
ak = a[k + 1 + (k + 1) * a_dim1] / akm1k;
denom = akm1 * ak - 1.;
i__1 = *nrhs;
for (j = 1; j <= i__1; ++j) {
bkm1 = b[k + j * b_dim1] / akm1k;
bk = b[k + 1 + j * b_dim1] / akm1k;
b[k + j * b_dim1] = (ak * bkm1 - bk) / denom;
b[k + 1 + j * b_dim1] = (akm1 * bk - bkm1) / denom;
}
k += 2;
}
goto L60;
L80:
k = *n;
L90:
if (k < 1) {
goto L100;
}
if (ipiv[k] > 0) {
if (k < *n) {
i__1 = *n - k;
dgemv_((char *)"Transpose", &i__1, nrhs, &c_b7, &b[k + 1 + b_dim1], ldb,
&a[k + 1 + k * a_dim1], &c__1, &c_b19, &b[k + b_dim1], ldb, (ftnlen)9);
}
kp = ipiv[k];
if (kp != k) {
dswap_(nrhs, &b[k + b_dim1], ldb, &b[kp + b_dim1], ldb);
}
--k;
} else {
if (k < *n) {
i__1 = *n - k;
dgemv_((char *)"Transpose", &i__1, nrhs, &c_b7, &b[k + 1 + b_dim1], ldb,
&a[k + 1 + k * a_dim1], &c__1, &c_b19, &b[k + b_dim1], ldb, (ftnlen)9);
i__1 = *n - k;
dgemv_((char *)"Transpose", &i__1, nrhs, &c_b7, &b[k + 1 + b_dim1], ldb,
&a[k + 1 + (k - 1) * a_dim1], &c__1, &c_b19, &b[k - 1 + b_dim1], ldb,
(ftnlen)9);
}
kp = -ipiv[k];
if (kp != k) {
dswap_(nrhs, &b[k + b_dim1], ldb, &b[kp + b_dim1], ldb);
}
k += -2;
}
goto L90;
L100:;
}
return 0;
}
#ifdef __cplusplus
}
#endif