VOBOZ/SingleHalo: single_halo.c

#include <stdio.h>
#include <stdlib.h>

int main(void){

  FILE *fout = fopen("single_halo.raw","wb");
  int i, j, k, counter = 0, np = 4*4*4 + 30;
  float *x_buf, *y_buf, *z_buf;
  float x, y, z;
  fwrite(&np,sizeof(int),1,fout);

  x_buf = (float *)malloc(np*sizeof(float));
  y_buf = (float *)malloc(np*sizeof(float));
  z_buf = (float *)malloc(np*sizeof(float));

  /* uniform grid */
  for(i = 0; i < 4; i++){
    x = ((float)i)/4.0+1.0/8.0;
    for(j = 0; j < 4; j++){
      y = ((float)j)/4.0+1.0/8.0;
      for(k = 0; k < 4; k++){
        z = ((float)k)/4.0+1.0/8.0;
        x_buf[counter] = x;
        y_buf[counter] = y;
        z_buf[counter++] = z;
      }
    }    
  }

  /* blob around (0.25, 0.25, 0.25) */
  for(j = 1; j < 4; j++){
    for(i = 0; i < 10; i++){
      x = 0.25 + j*0.05*(1.0 - 2.0*rand()/((float)RAND_MAX));
      y = 0.25 + j*0.05*(1.0 - 2.0*rand()/((float)RAND_MAX));
      z = 0.25 + j*0.05*(1.0 - 2.0*rand()/((float)RAND_MAX));
      x_buf[counter] = x;
      y_buf[counter] = y;
      z_buf[counter++] = z;
    }
  }

  fwrite(x_buf,sizeof(float),np,fout);
  fwrite(y_buf,sizeof(float),np,fout);
  fwrite(z_buf,sizeof(float),np,fout);

  free(y_buf);
  free(z_buf);

  fclose(fout);

  /* velocities */
  fout = fopen("single_halo_vel.raw","wb"); 
  fwrite(&np,sizeof(int),1,fout);
  for(i = 0; i < np; i++){
    x_buf[i] = 0.0;
  }

  fwrite(x_buf,sizeof(float),np,fout);
  fwrite(x_buf,sizeof(float),np,fout);
  fwrite(x_buf,sizeof(float),np,fout);
  fclose(fout);

  return 0;
}