postProcess/getDataSlice.c

#include “navier-stokes/centered.h”

char filename[512]; int nx, ny; double xmin, ymin, xmax, ymax; scalar * list = NULL; scalar f[];

int main(int a, char const *arguments[]){

L0 = 40; origin(-0.5L0, -0.5L0);

if (a != 8) { fprintf (stderr, “usage: getDataSlice xmin xmax ymin ymax nx ny”); return 1; } if (snprintf (filename, sizeof(filename), “%s”, arguments[1]) >= (int) sizeof(filename)) { fprintf (stderr, “error: snapshot path longer than %zu characters”, sizeof(filename) - 1); return 1; } xmin = atof(arguments[2]); xmax = atof(arguments[3]); ymin = atof(arguments[4]); ymax = atof(arguments[5]); nx = atoi(arguments[6]); ny = atoi(arguments[7]); if (nx <= 0 || ny <= 0 || !(xmax > xmin) || !(ymax > ymin)) { fprintf (stderr, “error: need xmax > xmin, ymax > ymin and positive nx, ny”); return 1; }

list = list_add (list, f); list = list_add (list, u.x); list = list_add (list, u.y);

if (!restore (file = filename)) { fprintf (stderr, “error: could not restore %s”, filename); return 1; } boundary((scalar *){f, u.x, u.y});

FILE * fp = ferr; nx++; ny++; double Deltax = 0.999999(xmax-xmin)/(nx - 1); double Deltay = 0.999999(ymax-ymin)/(ny - 1); int len = list_len(list); double ** field = (double **) matrix_new (nx, ny, lensizeof(double)); for (int i = 0; i < nx; i++) { double x = Deltaxi + xmin; for (int j = 0; j < ny; j++) { double y = Deltay*j + ymin; int k = 0; for (scalar s in list){ field[i][len*j + k++] = interpolate (s, x, y); } } }

for (int i = 0; i < nx; i++) { double x = Deltaxi + xmin; for (int j = 0; j < ny; j++) { double y = Deltayj + ymin; fprintf (fp, “%g %g”, x, y); int k = 0; for (scalar s in list){ fprintf (fp, ” %g”, field[i][len*j + k++]); } fputc (‘’, fp); } } fflush (fp); matrix_free (field);

}