c - Assigning integers from a file to an array -

edit: tried suggestions , didn't alter kind of works gives me incorrect data atleast aren't zeros. thier assistance.

i'm writing code reading grades text file , store them in array. full code rather large i'm posting part having issue in; while loop not changing values in array. sample data 65 99 87 76 89 37 -999 on separate lines. output shows me array values remained 0 after function should have changed values. other while loops failed attempts @ same task.

int readgrades(double grades[]){     file* gd;     int count = 0;     double ind;     gd = fopen("sample.txt", "r");      while(count < max){ //max defined 100/array grades[max]     fscanf(gd, "%lf", &ind); //should scan through items in file      if(ind < 0) //end of sample data -999 breaks out of loop         break;     grades[count] = ind; //changes values in array (it doesn't change them 0)     count++; } //increments index of array     /*while(fscanf(gd, "%lf", &ind)>0){     grades[count] = ind;     count++; }*/     /*do {         fscanf(gd, "%lf", &grades[count]);         printf("%.0lf", grades[count]);         if(fscanf(gd, "%lf", &grades[count])== -999){             break;         }         count++;    }while(fscanf(gd, "%lf", &grades[count])> 0);*/     fclose(gd);     return count+1; } 

some info: grades array has initialized double filled w/ 0s. need replace zeros in grades[] data text file. i've been working on over day , still have had 0 progress. don't understand why doesn't change values in array.

edit: call readgrades array data.

int numgrades;  numgrades = readgrades(grades); 

right inside main. #define max 100 , double grades[max] delcared outside main. return count+1 function needs return number of data items read.

someone asked full program:

#include <stdio.h> #include <stdlib.h> #include <math.h>  int readgrades(double []); void frequency(double [], int); int maximum(double [], int); int minimum(double [], int); int deleteelement(double [], int, int); double mean(double [], int); double standarddeviation(double [], int); #define max 100 double grades[max]; int loc;  int main(){     int numgrades;     printf("%lf", grades);     numgrades = readgrades(grades);     loc = minimum(grades, numgrades);     numgrades = deleteelement(grades, numgrades, loc);     printf("the data has been adjusted removing minimum %.2lf\n", grades[loc]);     loc = maximum(grades, numgrades);     numgrades = deleteelement(grades, numgrades, loc);     printf("the data has been adjusted removing maximum %.2lf\n", grades[loc]);     printf("the adjusted mean %.2lf\n", mean(grades, numgrades));     printf("the adjusted standard deviation %.2lf\n",       standarddeviation(grades, numgrades));     printf("here histogram of adjusted data:\n");     frequency(grades, numgrades);     return 0; } int readgrades(double grades[]){     file* gd;     int count = 0;     double ind;     gd = fopen("sample.txt", "r");     while(count < max){         fscanf(gd, "%lf", &ind);     //double atod(ind);         if(ind < 0)            break;     grades[count] = ind;     count++; }  /*while(fscanf(gd, "%lf", &ind)>0){     grades[count] = ind;     count++; }*/ /*do {         fscanf(gd, "%lf", &grades[count]);         printf("%.0lf", grades[count]);         if(fscanf(gd, "%lf", &grades[count])== -999){             break;         }         count++; }while(fscanf(gd, "%lf", &grades[count])> 0);*/ printf("%.0lf", grades[1]); fclose(gd); return count+1; } void frequency(double grades[], int numgrades){     int j, i, a=0, b=a+4;     for(j=0; j<numgrades-1; j++){         printf("%d - %d|", a, b);         for(i=0; i<numgrades; i++){             if(grades[i]<=b && grades[i]>=a){                 printf("*");         }     }     printf("\n");     a+=5;     if(a==100){         break;     } } printf("%d|", a); for(j=0; j<numgrades; j++){     if(grades[i]==100)         printf("*"); } printf("\n"); }  int maximum(double grades[], int numgrades){     int i, h = 0;     for(i=1; i<numgrades; i++){     /*if(grades[i] == grades[h])         continue;*/     if(grades[i] > grades[h])         h = i; } return h; }  int minimum(double grades[], int numgrades){     int i, h = 0;     for(i=1; i<numgrades; i++){     /*if(grades[i] == grades[h])         continue;*/     if(grades[i] < grades[h])         h = i; }     return h; } int deleteelement(double grades[], int numgrades, int loc){     int i;     for(i=loc; i<numgrades-1; i++){     grades[i] = grades[i+1];     }     return numgrades-=1; } double mean(double grades[], int numgrades){     int i;     double ans, sum;     for(i = 0; i<numgrades; i++){     sum += grades[i]; }     ans = sum/numgrades;     return ans; } double standarddeviation(double grades[], int numgrades){     int i;     double avg, sd, ans;     avg = mean(grades, numgrades);     for(i=0; i<numgrades; i++){     sd += pow((avg - grades[i]), 2); }     ans = sqrt(sd/numgrades);     return ans; } 

i appreciate helping me this.

check result of fopen , fscanf calls:

gd = fopen( "sample.txt", "r" ); if ( !gd ) {   fprintf( stderr, "error opening input file\n" );   return 0; }  while( count < max && fscanf( gd, "%lf", &ind ) == 1 ) {   if ( ind < 0 )     break;   grades[count++] = ind; }  if ( feof( gd ))   fprintf( stderr, "hit end of file\n" ); else if ( ferror( gd ))   fprintf( stderr, "error during read\n" );