Cannot convert from 'int' to 'int []' error

[fjf314]

I'm currently writing a program that reads information from an already created file, and displays the information in an array. I created one function that takes the data from the file and places it in the array. I created a second function to output the array. However, when I place my function to output the the array within my int main(), I get the following error:

error C2664: 'display_array' : cannot convert parameter 1 from 'int' to 'int []'

This might be something simple, but I'm new with arrays. Here is my code:

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


void program_description();
void get_info_from_file( ifstream &i_file, int arr[], int &no_items );
void display_array( int arr[], int no_items );

const int max_list = 50;

int main()
{
	//Variable Declarations
	int number;
	int no_values;
	int array[max_list];
	ifstream in_file;

	no_values = 0;

	program_description();

	display_array( array[max_list], no_values );


	return 0;
}

//Function Definitions

void program_description()
/*=======================================================================================
This function outputs a description of the program to the user.
	INPUT: None
	OUTPUT: None
=======================================================================================*/
{
	cout << "Greetings!  This program is designed to take the ";
	cout << "data\ncurrently stored in another file and display it to you.  It will then ";
	cout << "sort the data, number it, and calculate the sum, range, mean, and median.  ";
	cout << "From there a\nhistogram of the data is displayed.\n\n";
}

void get_info_from_file( ifstream &i_file, int arr[], int &no_items )
/*=======================================================================================
This function opens the input stream, gets the data from the file one item at a time, and 
stores each item in an array element.  It also counts the number of items in the file.  
Lastly, the input stream is closed.
	INPUT: A parameter of type ifstream, an array of integers, an integer which
			represents the number of items in the file.
	OUTPUT: This function returns nothing.
=======================================================================================*/
{
	int data;
	no_items = 0;

	i_file.open("stat_data");
	i_file >> data;
	arr[no_items] = data;
	no_items ++;

	while ( ! i_file.eof() );
	{
		i_file >> data;
		arr[no_items] = data;
		no_items ++;
	}
}

void display_array( int arr[], int no_items )
/*=======================================================================================
The function traverses the array of integers, outputting each element in the array.
	INPUT: an array of integers, an integer which represents the number of items in
			the file.
	OUTPUT: This function returns nothing.
=======================================================================================*/
{
	int no_scores;
	no_scores = 0;
	
	for ( int i = 0; i < no_scores; i++ )
	{
		cout << arr[i] << " ";
	}
}

[alphaoide]

When you pass the array to a function, do it like this.

display_array( array, max_list, no_values );

[fjf314]

When I do that, then, how should I go about changing my function? If I leave my function as is, then I'll get an error on having three parameters.

[alphaoide]

something like this for the prototype and definition

void display_array( int arr[], int max, int no_items )

[fjf314]

Well, the error problem is solved, but the program itself doesn't seem to be working... Are there any other apparent errors?

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


void program_description();
void get_info_from_file( ifstream &i_file, int arr[], int &no_items );
void display_array( int arr[], int max, int no_items );

const int max_list = 50;

int main()
{
	//Variable Declarations
	int number;
	int no_values;
	int array[max_list];
	ifstream in_file;

	no_values = 0;

	program_description();

	display_array( array, max_list, no_values );


	return 0;
}

//Function Definitions

void program_description()
/*========================================================================
This function outputs a description of the program to the user.
	INPUT: None
	OUTPUT: None
========================================================================*/
{
	cout << "Greetings!  This program is designed to take the ";
	cout << "data currently stored in\nanother file and display it to you.  It will then ";
	cout << "sort the data, number it,\nand calculate the sum, range, mean, and median.  ";
	cout << "From there a\nhistogram of the data is displayed.\n\n";
}

void get_info_from_file( ifstream &i_file, int arr[], int &no_items )
/*========================================================================
This function opens the input stream, gets the data from the file one item at a time, and 
stores each item in an array element.  It also counts the number of items in the file.  
Lastly, the input stream is closed.
	INPUT: A parameter of type ifstream, an array of integers, an integer which
			represents the number of items in the file.
	OUTPUT: This function returns nothing.
========================================================================*/
{
	int data;
	no_items = 0;

	i_file.open("stat_data");
	i_file >> data;
	arr[no_items] = data;
	no_items ++;

	while ( ! i_file.eof() );
	{
		i_file >> data;
		arr[no_items] = data;
		no_items ++;
	}
}

void display_array( int arr[], int max, int no_items )
/*========================================================================
The function traverses the array of integers, outputting each element in the array.
	INPUT: an array of integers, an integer which represents the number of items in
			the file.
	OUTPUT: This function returns nothing.
========================================================================*/
{
	int no_scores;
	no_scores = 0;
	
	for ( int i = 0; i < no_scores; i++ )
	{
		cout << arr[i] << " ";
	}
}

[alphaoide]

void program_description();
void get_info_from_file( ifstream &i_file, int arr[], int &no_items );

I suppose you want to call those functions from main().

[swoopy]

> program_description();

> display_array( array, max_list, no_values );

As Alphaoide said, you need to call get_info_from_file() here:
program_description();
get_info_from_file( in_file, array, no_values );
display_array( array, max_list, no_values );

void display_array( int arr[], int max, int no_items )
/ *=================================================
=======================
The function traverses the array of integers, outputting each element in the array.
	INPUT: an array of integers, an integer which represents the number of items in
			the file.
	OUTPUT: This function returns nothing.
 ==================================================
======================*/
{
	int no_scores;
	no_scores = 0;
	
	for ( int i = 0; i < no_scores; i++ )
	{
		cout << arr[i] << " ";
	}
}

This should be:

void display_array( int arr[], int no_items )
/ *=================================================
=======================
The function traverses the array of integers, outputting each element in the array.
	INPUT: an array of integers, an integer which represents the number of items in
			the file.
	OUTPUT: This function returns nothing.
 ==================================================
======================*/
{
	for ( int i = 0; i < no_items; i++ )
	{
		cout << arr[i] << " ";
	}
}

[alphaoide]

Originally posted by alphaoide
something like this for the prototype and definition

void display_array( int arr[], int max_list, int no_items )

Sorry, but I missed it. In your program max_list is a global variable so you don't actually need to pass it.

void display_array( int arr[], int no_items )

But, you should've known that, though

[fjf314]

Well, I was able to get my program running at school today. I've started to add some more things, but now I've noticed that my array is acting up. It's repeating the last number in my stat_data file twice. So if the numbers in my file are: 98, 54, 76, 46, and 78 my program outputs: 98, 54, 76, 46, 78, and 78. Sorry for all of the pleas for help, but this is really getting frustrating. Here's my code:

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


void program_description();
void get_info_from_file( ifstream &i_file, int arr[], int &no_items );
void display_array( int arr[], int no_items );
void sort_ascending( int arr[], int no_items );
int get_total( int arr[], int no_items );
int calc_range( int arr[], int no_items );

const int max_list = 50;

int main()
{
	//Variable Declarations
	int no_values;
	int array[max_list];
	ifstream in_file;

	no_values = 0;

	program_description();

	get_info_from_file( in_file, array, no_values );

	display_array( array, no_values );

	sort_ascending( array, no_values );

	get_total( array, no_values );


	return 0;
}

//Function Definitions

void program_description()
/*========================================================================
This function outputs a description of the program to the user.
	INPUT: None
	OUTPUT: None
========================================================================*/
{
	cout << "Greetings!  This program is designed to take the ";
	cout << "data currently stored in\nanother file and display it to you.  It will then ";
	cout << "sort the data, number it,\nand calculate the sum, range, mean, and median.  ";
	cout << "From there a histogram\nof the data is displayed.\n\n";
}

void get_info_from_file( ifstream &i_file, int arr[], int &no_items )
/*========================================================================
This function opens the input stream, gets the data from the file one item at a time, and 
stores each item in an array element.  It also counts the number of items in the file.  
Lastly, the input stream is closed.
	INPUT: A parameter of type ifstream, an array of integers, an integer which
			represents the number of items in the file.
	OUTPUT: This function returns nothing.
========================================================================*/
{
	int data;
	no_items = 0;

	i_file.open("stat_data");
	i_file >> data;
	arr[no_items] = data;
	no_items ++;
	
	
	while ( ! i_file.eof() )
	{
		i_file >> data;
		arr[no_items] = data;
		no_items ++;
	}

	i_file.close();

	cout << "The number of items in this array is: " << no_items;
	cout << endl << endl;

	cout << "The array is:\n\n";

	
}

void display_array( int arr[], int no_items )
/*========================================================================
The function traverses the array of integers, outputting each element in the array.
	INPUT: an array of integers, an integer which represents the number of items in
			the file.
	OUTPUT: This function returns nothing.
========================================================================*/
{
	for ( int i = 0; i < no_items; i++ )
	{
		cout << arr[i] << " ";
	}

	cout << endl << endl;
}

void sort_ascending( int arr[], int no_items )
/*========================================================================
This function sorts an array of integers in ascending order using a selection sort.
	INPUT: an array of integers, an integer which represents the number of items.
	OUPUT: This function returns nothing.
========================================================================*/
{
	int i, hold;

	cout << "This is the array sorted in ascending order: " << endl << endl;
	
	for ( int pass = 0; pass < no_items - 1; pass++ )

		for ( i = 0; i < no_items - 1; i++ )

			if (arr[i] > arr[i + 1] )
			{
				hold = arr[i];
				arr[i] = arr[i +1];
				arr[i+1] = hold;
			}

	for ( i = 0; i < no_items; i++ )
		cout << arr[i] << " ";
		cout << endl;

	cout << endl << endl;

}

int get_total( int arr[], int no_items )
/*========================================================================
This function traverses the array of integers and totals the elements in the array.
	INPUT: an array of integers, an integer which represents the number of items 
			in the file
	OUPUT: This function returns an integer which represents the total of all of
			the elements.
========================================================================*/
{
	int sum;

	sum = 0;

	for ( int i = 0; i < no_items; i++ )
	{
		sum = arr[i]+sum;
	}

	cout << "The sum of all the data is: " << sum << endl << endl;

	return sum;
}

[swoopy]

>	
>	while ( ! i_file.eof() )
>	{
>		i_file >> data;
>		arr[no_items] = data;
>		no_items ++;
>	}

eof isn't seen until a read is attempted at the end of file (see the Programming FAQ), so you can either use:

	while ( i_file >> data )
	{
		arr[no_items] = data;
		no_items ++;
	}

Or something like:

	while ( ! i_file.eof() )
	{
		i_file >> data;
		if ( !i_file.eof() )
		{
			arr[no_items] = data;
			no_items ++;
		}
	}