Files
AMSS-NCKU/AMSS_NCKU_source/xh_fderivs.C
2026-03-01 05:48:40 +08:00

145 lines
4.9 KiB
C
Raw Blame History

This file contains ambiguous Unicode characters
This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.
#include "xh_tool.h"
/*
* C 版 fderivs
*
* Fortran:
* subroutine fderivs(ex,f,fx,fy,fz,X,Y,Z,SYM1,SYM2,SYM3,symmetry,onoff)
*
* 约定:
* f, fx, fy, fz: ex1*ex2*ex3按 idx_ex 布局
* X: ex1, Y: ex2, Z: ex3
*/
void fderivs(const int ex[3],
const double *f,
double *fx, double *fy, double *fz,
const double *X, const double *Y, const double *Z,
double SYM1, double SYM2, double SYM3,
int Symmetry, int onoff)
{
(void)onoff; // Fortran 里没用到
const double ZEO = 0.0, ONE = 1.0;
const double TWO = 2.0, EIT = 8.0;
const double F12 = 12.0;
const int NO_SYMM = 0, EQ_SYMM = 1; // OCTANT=2 在本子程序里不直接用
const int ex1 = ex[0], ex2 = ex[1], ex3 = ex[2];
// dX = X(2)-X(1) -> C: X[1]-X[0]
const double dX = X[1] - X[0];
const double dY = Y[1] - Y[0];
const double dZ = Z[1] - Z[0];
int iminF = 1, jminF = 1, kminF = 1;
if (Symmetry > NO_SYMM && fabs(Z[0]) < dZ) kminF = -1;
if (Symmetry > EQ_SYMM && fabs(X[0]) < dX) iminF = -1;
if (Symmetry > EQ_SYMM && fabs(Y[0]) < dY) jminF = -1;
// SoA(1:3) = SYM1,SYM2,SYM3
const double SoA[3] = { SYM1, SYM2, SYM3 };
// fh: (ex1+2)*(ex2+2)*(ex3+2) because ord=2
const size_t nx = (size_t)ex1 + 2;
const size_t ny = (size_t)ex2 + 2;
const size_t nz = (size_t)ex3 + 2;
const size_t fh_size = nx * ny * nz;
static thread_local double *fh = NULL;
static thread_local size_t cap = 0;
if (fh_size > cap) {
free(fh);
fh = (double*)aligned_alloc(64, fh_size * sizeof(double));
cap = fh_size;
}
// double *fh = (double*)malloc(fh_size * sizeof(double));
if (!fh) return;
// call symmetry_bd(2,ex,f,fh,SoA)
symmetry_bd(2, ex, f, fh, SoA);
const double d12dx = ONE / F12 / dX;
const double d12dy = ONE / F12 / dY;
const double d12dz = ONE / F12 / dZ;
const double d2dx = ONE / TWO / dX;
const double d2dy = ONE / TWO / dY;
const double d2dz = ONE / TWO / dZ;
// fx = fy = fz = 0
const size_t all = (size_t)ex1 * (size_t)ex2 * (size_t)ex3;
for (size_t p = 0; p < all; ++p) {
fx[p] = ZEO;
fy[p] = ZEO;
fz[p] = ZEO;
}
/*
* Fortran loops:
* do k=1,ex3-1
* do j=1,ex2-1
* do i=1,ex1-1
*
* C: k0=0..ex3-2, j0=0..ex2-2, i0=0..ex1-2
*/
for (int k0 = 0; k0 <= ex3 - 2; ++k0) {
const int kF = k0 + 1;
for (int j0 = 0; j0 <= ex2 - 2; ++j0) {
const int jF = j0 + 1;
for (int i0 = 0; i0 <= ex1 - 2; ++i0) {
const int iF = i0 + 1;
const size_t p = idx_ex(i0, j0, k0, ex);
// if(i+2 <= imax .and. i-2 >= imin ... ) (全是 Fortran 索引)
if ((iF + 2) <= ex1 && (iF - 2) >= iminF &&
(jF + 2) <= ex2 && (jF - 2) >= jminF &&
(kF + 2) <= ex3 && (kF - 2) >= kminF)
{
fx[p] = d12dx * (
fh[idx_fh_F_ord2(iF - 2, jF, kF, ex)] -
EIT * fh[idx_fh_F_ord2(iF - 1, jF, kF, ex)] +
EIT * fh[idx_fh_F_ord2(iF + 1, jF, kF, ex)] -
fh[idx_fh_F_ord2(iF + 2, jF, kF, ex)]
);
fy[p] = d12dy * (
fh[idx_fh_F_ord2(iF, jF - 2, kF, ex)] -
EIT * fh[idx_fh_F_ord2(iF, jF - 1, kF, ex)] +
EIT * fh[idx_fh_F_ord2(iF, jF + 1, kF, ex)] -
fh[idx_fh_F_ord2(iF, jF + 2, kF, ex)]
);
fz[p] = d12dz * (
fh[idx_fh_F_ord2(iF, jF, kF - 2, ex)] -
EIT * fh[idx_fh_F_ord2(iF, jF, kF - 1, ex)] +
EIT * fh[idx_fh_F_ord2(iF, jF, kF + 1, ex)] -
fh[idx_fh_F_ord2(iF, jF, kF + 2, ex)]
);
}
// elseif(i+1 <= imax .and. i-1 >= imin ...)
else if ((iF + 1) <= ex1 && (iF - 1) >= iminF &&
(jF + 1) <= ex2 && (jF - 1) >= jminF &&
(kF + 1) <= ex3 && (kF - 1) >= kminF)
{
fx[p] = d2dx * (
-fh[idx_fh_F_ord2(iF - 1, jF, kF, ex)] +
fh[idx_fh_F_ord2(iF + 1, jF, kF, ex)]
);
fy[p] = d2dy * (
-fh[idx_fh_F_ord2(iF, jF - 1, kF, ex)] +
fh[idx_fh_F_ord2(iF, jF + 1, kF, ex)]
);
fz[p] = d2dz * (
-fh[idx_fh_F_ord2(iF, jF, kF - 1, ex)] +
fh[idx_fh_F_ord2(iF, jF, kF + 1, ex)]
);
}
}
}
}
// free(fh);
}