Thread: Undefined Reference Problem

I can't seem to find out the problem here. If anyone could help me, that would be great.

Compiler output:
c:\windows\TEMP\ccTo2Afb.o(.text+0x6b):histog~1.cp p: undefined reference to `average_numbers(int *, int)'
c:\windows\TEMP\ccTo2Afb.o(.text+0xd0):histog~1.cp p: undefined reference to `make_frequency(int *, int, int *, int)'
c:\windows\TEMP\ccTo2Afb.o(.text+0xe4):histog~1.cp p: undefined reference to `make_histogram(int *, int)'

Program:

#include <iostream.h>
#include <stdlib.h>
#include <iomanip.h>
#include <fstream.h>

const int MAX_ELMNTS = 100;
const int ANLYS_RNG = 19;

// ===========Open input file===========
// Gets the name of the input file and opens it for input

void open_input_file ( ifstream &in_file );
// =============Get Data============
// Read data from the file into the array. The array may not be completely
// filled. It will use what is there and discard any extra data.

int get_data
( int numbers[], int size, int range );

// ============Print Data=============
// Print the data as a 2-dimensional array.

void print_data
( const int numbers[], int size, int line_size );

// ============Average Numbers===========
// Reckons the average of the numbers in the array.

float average_numbers
( int numbers[], int size);

// ===========Make Frequency==========
// Puts the frequency count into an array.

void make_frequency
( int numbers[], int size, int frequency[], int range );

// ==============Make histogram========
// Prints the histogram based on the frequency counts.

void make_histogram
( int frequency[], int range );

// ===============main==============
int main()
{
// Local Declarations
int size;
int nums[MAX_ELMNTS];
int frequency[ANLYS_RNG + 1];

// Statements
size = get_data( nums, MAX_ELMNTS, ANLYS_RNG );

cout << "The average of the numbers is "
<< average_numbers( nums, size )
<< endl;

print_data( nums, size, 10 );

make_frequency( nums, size, frequency, ANLYS_RNG );
make_histogram( frequency, ANLYS_RNG );

system("PAUSE");
return 0;
}

// ==========Open Input File===============
void open_input_file
( ifstream &in_file )
{ char in_file_name[80];

cout << "Enter the input file name: ";
cin >> in_file_name;

in_file.open(in_file_name);
if (!in_file)
cerr << "Error opening file\a\a\n", exit(100);
}
// ===========Average Numbers=============
float average_numbers
( const int numbers[], int size )
{ float sum = 0.0;
int i;

for (i = 0; i < size; i++ )
sum = float( numbers[i] ) + sum;
if (size != 0)
{ return (sum/float(size)); }
else
{ cout << "No values entered \n";
exit (101);
}
}
// =============Get Data===============
int get_data
( int numbers[], int size, int range )
{
int data_in;
int loader = 0;
ifstream fs_data;

open_input_file (fs_data);

while (loader < size && (fs_data >> data_in))
{
if (data_in >= 0 && data_in <= range)
numbers[loader++] = data_in;
else
cout << "Data point " << data_in
<< " invalid. Ignored. \n";
}

if (loader == size && (fs_data >> data_in))
cout << "\nToo much data. Will process what was read. \n";
return loader;
}
//==============Print Data===============
void print_data
( const int numbers[], int size, int line_size )
{
int i;
int num_printed = 0;

cout << endl << endl;

for (i = 0; i < size; i++)
{
num_printed++;
cout << setw(4) << numbers[i];
if (num_printed >= line_size)
{
cout << endl;
num_printed = 0;
}
}
cout << endl << endl;
return;
}
//==============Make Frequency==========
void make_frequency
( const int numbers[], int size, int frequency[], int range )
{
int i;

for (i = 0; i <= range; i++)
frequency[i] = 0;
for (i = 0; i <= size; i++)
frequency[numbers[i]] = frequency[numbers[i]] + 1;

return;
}
//=============Make Histogram============
void make_histogram
( const int frequency[], int range )
{
int i;
int j;

for (i = 0; i <= range; i++)
{
cout << setw(3) << i << setw(3) << frequency[i];
for (j = 1; j <= frequency[i]; j++)
cout << "*";
cout << endl;
}
return;
}