Programming Forums - array issue

Programming Forums (http://www.programmingforums.org/forumindex.php)

- C++ (http://www.programmingforums.org/forum15.html)

- - array issue (http://www.programmingforums.org/showthread.php?t=15727)

2 questions first did the main daniweb site get hacked or something...2nd can someone take a look at my code and see what I am doing wrong...can't seem to pinpoint it

Not sure what I am doing wrong but have an issue with a program...i am to input a file name that i have in my project and it is not doing it right...

This is what my program should look like for each textfile...

Sample Output 1
Enter the file to read in: data1.txt
The numbers in the array are:

45.3 57.4 23.6 34.2
234.6 34.9 54.8 934.9
8432.5 9809.3 539.7 43.9
12.0

The numbers in the array are:

12.0 23.6 34.2 34.9
43.9 45.3 54.8 57.4
234.6 539.7 934.9 8432.5
9809.3

The average of the numbers is 1558.2
The median of the numbers is 54.8

Press any key to continue

What I am getting is...

Enter the file to read in: data1.txt

The numbers in the array are:

The average of the numbers is 45
The median of the numbers is 0

Press any key to continue...

Not sure what I am doing wrong any help would mean alot

 
#include <iostream>
#include <fstream>
#include <iomanip>
#include <string>
using namespace std;
 
const int MAX_SIZE = 100;
 
void Fill_Array(int Size[], int& count, int& numbers_used);
void Print_Array(int Size[], int count);
double Calc_Average(int Size[], double average);
void Sort(int Size[], int numbers_used);
void Swap(int& v1, int& v2);
int index_of_smallest(const int Size[], int start_index, int number_used);
int Calc_Median(int median, int Size[]);
void Print_Array_and_Calculations(int median, double average);
 
int main()
{
        ifstream in_size;
        int count;
        int Size [MAX_SIZE],
            numbers_used = 0,
            median = 0;
        double average = 0.0;
 
        Fill_Array(Size, count, numbers_used);
        Print_Array(Size, count);
        average = Calc_Average(Size, average);
        Sort(Size, numbers_used);
        Calc_Median(median, Size);
        Print_Array_and_Calculations(median, average);
 
        in_size.close();
        return 0;
}
 
void Fill_Array(int Size[], int& count, int& numbers_used)
{
        int size;
        ifstream in_size;
        string text_file;
 
 
        cout << "Enter the file to read in: ";
        getline(cin, text_file);
 
        cout << endl << "The numbers in the array are:" << endl << endl;
        in_size.open (text_file.c_str ());
        if(in_size.fail())
        {
                cerr  << "Error opening file" << endl;
                exit(1);
        }
        count = 0;
        in_size >> size;
        while((!in_size.eof()) && (count <= MAX_SIZE))
        {
                Size[count] = size;
                count++;
                in_size >> size;
        }
        in_size.close();
}
 
void Print_Array(int Size[], int count)
{
        int number_used = 0;
        for(int index = 0; index < number_used; index++)
                cout << Size[index] << " ";
}
 
double Calc_Average(int Size[], double average)
{
        int total = 0;
        for (int i = 0; i < MAX_SIZE; i++)
        {
                total = total + Size[i];
        }
        average = double(total) / MAX_SIZE;
 
        return average;
}
 
void Sort(int Size[], int number_used)
{
        int index_of_next_smallest;
 
        for (int index = 0; index < number_used - 1; index++)
        {
                index_of_next_smallest = index_of_smallest(Size, index, number_used);
                Swap(Size[index], Size[index_of_next_smallest]);
        }
}
 
void Swap(int& v1, int& v2)
{
        int temp;
        temp = v1;
        v1 = v2;
        v2 = temp;
}
 
int index_of_smallest(const int Size[], int start_index, int number_used)
{
        int min = Size[start_index],
                index_of_min = start_index;
        for (int index = start_index + 1; index < number_used; index++)
                if(Size[index] < min)
                {
                        min = Size[index];
                        index_of_min = index;
                }
                return index_of_min;
}
 
int Calc_Median(int median, int Size[])
{
        median = Size [ MAX_SIZE / 2 ];
        return median;
}
 
void Print_Array_and_Calculations(int median, double average)
{
        cout << endl << "The average of the numbers is " << average;
        cout << endl << "The median of the numbers is " << median;
        cout << endl << endl;
}

Here's something that does pretty much the same thing. I wrote it earlier this semester for my principle of programming languages class:

#include <iostream>

#include <fstream>

#include <string>

#include <math.h>

#include <exception>

using namespace std;



// Parses the input file into the array's size and contents.

// Dynamically allocates memory for the array, fills it, and returns.

void parse_file(char * filename, double *&a, int &size) {

        ifstream myfile;

        myfile.exceptions( fstream::failbit );



        // Get the file name, and try to open the said file

        printf("Input the filename: ");   

        scanf("%s",filename);

        // Try opening the file, if it doesn't exist, throw an exception

        try {

                myfile.open(filename);

        } catch(ifstream::failure e) {

                printf("File does not exist or is unreadable\n");

        }



        // Read the first thing from the file as an int and store it as 'num'

        myfile>>size;



        // allocate an array to the exact that we need

        a = (double *) malloc(size*sizeof(double));

        // Fill the array

        for(int i=0; i<size; i++) {

                myfile>>a[i];

        }

        myfile.close();

}



// Standard way of calculating average

// Sums the elements of a, puts them into total, divides by size and returns.

double find_average(double *&a, int size) {

        double total = 0;

        for(int i=0; i<size; i++) {

                total = total + a[i];

        }

        return (total/(double)size);

}



// Standard way of calculating standard deviation

// Sums the square of each element minus the average

// Divides the total of squares by the size and returns the positive square root of the sum.

double find_standard_dev(double *&a, int size, double average) {

        double dev = 0;

        for(int i=0; i<size; i++) {

                dev = dev + pow(a[i]-average,2);

        }

        dev = dev/size;

        return (sqrt(fabs(dev)));

}



int main() {



        // Set up some variables

        char filename[50]; // 50 characters for the filename should be good enough unless the path is included.

        double average = 0, standard_dev = 0; // Zero out our variables before we start using them

        int num; // Array size

        double * array; // Make a pointer to our array



        parse_file(filename, array, num);



        average = find_average(array,num);



        standard_dev = find_standard_dev(array, num, average);



        printf("Average: %lf\n",average);

        printf("Standard Deviation: %lf\n",standard_dev);

        free(array);

        return 0;

}

In your Fill_Array function, you don't set the number_used variable to the number of items found.

In your print_array function:

void Print_Array(int Size[], int count)

{

        int number_used = 0;

        for(int index = 0; index < number_used; index++)

                cout << Size[index] << " ";

}

You should use the count that is passed in, rather than the number_used variable that is set to 0

The Calc_Average and Calc_Median functions need to be passed the number of items in the array, rather than using MAX_SIZE

Also, your array is of type int, and the input has floating point numbers, you should look into using type double.

Guess no one has answered his first question, the ALMIGHTY Dannyo329 has answered:
I Do Not Think So.( I was just on it , not sure at the time when you posted your questions though.)