dgetrs.c

来自「最著名最快的分子模拟软件」· C语言 代码 · 共 54 行

#include "gmx_blas.h"
#include "gmx_lapack.h"

void
F77_FUNC(dgetrs,DGETRS)(char *trans, 
	int *n, 
	int *nrhs, 
	double *a, 
	int *lda, 
	int *ipiv,
	double *b, 
	int *ldb, 
	int *info)
{
    int a_dim1, a_offset, b_dim1, b_offset;
    int notran;
    int c__1 = 1;
    int c_n1 = -1;
    double one = 1.0;

    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;
    notran = (*trans=='N' || *trans=='n');

    if (*n <= 0 || *nrhs <= 0) 
	return;

    if (notran) {
	F77_FUNC(dlaswp,DLASWP)(nrhs, &b[b_offset], ldb, &c__1, n, &ipiv[1], &c__1);
	F77_FUNC(dtrsm,DTRSM)("Left", "Lower", "No transpose", "Unit", n, nrhs, &one, 
	       &a[a_offset], lda, &b[b_offset], ldb);

	F77_FUNC(dtrsm,DTRSM)("Left", "Upper", "No transpose", "Non-unit", n, nrhs, &one, 
	       &a[a_offset], lda, &b[b_offset], ldb);
    } else {
	F77_FUNC(dtrsm,DTRSM)("Left", "Upper", "Transpose", "Non-unit", n, nrhs, &one, 
	       &a[a_offset], lda, &b[b_offset], ldb);
	F77_FUNC(dtrsm,DTRSM)("Left", "Lower", "Transpose", "Unit", n, nrhs, &one, 
	       &a[a_offset], lda, &b[b_offset], ldb);

	F77_FUNC(dlaswp,DLASWP)(nrhs, &b[b_offset], ldb, &c__1, n, &ipiv[1], &c_n1);
    }

    return;

}