Read files in C

main.c

#include <stdlib.h>
#include <stdio.h>
#include <math.h>
#define MAXNUM 100

typedef struct Person
{
  double height;
  double weight;
} Person;

int getData(char filename[], Person people[])
{
  FILE *data;
  int c = 0;
  int i = 0;
  double height, weight;

  data = fopen(filename, "r");
  if (data == NULL)
  {
    printf("Unable to open file\n");
    exit(1);
  }
  while(c < MAXNUM)
  {
    int ret = fscanf(data, "%lf, %lf", &height, &weight);
    if (ret == EOF) {
      break;
    }
    people[c].height = height;
    people[c].weight = weight;
    c++;
  }
  fclose(data);
  return c;
}

double getAverage(int data[], int length) {
  int i, sum;
  sum = 0;
  for (i = 0; i < length; i++) {
    sum += data[i];
  }
  return sum / length;
}

int main(int argc, char **argv)
{
  char filename[] = "values.dat";
  Person people[MAXNUM];
  int numPeople, heightData[numPeople], weightData[numPeople];
  double aveHeight, aveWeight, stdHeight, stdWeight;

  numPeople = getData(filename, people);

  for (int i = 0; i < numPeople; i++) {
    heightData[i] = people[i].height;
    weightData[i] = people[i].weight;
  }

  printf("The average height is %lf\n", getAverage(heightData, numPeople));
  printf("The average weight is %lf\n", getAverage(weightData, numPeople));
}