gistfile1.txt

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

int main()
{ 
  FILE *f = fopen("test.txt", "r");
  double array[3][10000];
  char line[1024];
  char *token;
  int i, j, k, l;

  i = 0;
  while(fgets(line, 1024, f))
  { 
    j = 0;
    for(token = strtok(line, ","); token != NULL; token = strtok(NULL, ","))
    { 
      array[j++][i] = atof(token);
    }

    i++;
  }

  for(k = 0; k < i; k++)
  { 
    for(l = 0; l < 3; l++)
    { 
      printf("%f ", array[l][k]);
    }
    printf("\n");
  }
}