2D arrays

[spicysalsa]

I'm working with 2D arrays. I'm reading information from a text file and printing out the information, also attaching that info to a 2D array. I need to calculate the sum and average of each row and column. I can figure out how to do the math, but I'm stumped on what to pass to my functions so I can use the array to calculate my rows and columns.

My first function worked with just getData() (it worked in main and the function itself) I want to include parameters but I'm not sure of the correct way to do it?

Can I use the same parameters all through the code?

int array2D[15][15];

//PROTOTYPES:
void getData(int i, int j);
void rowsum();


//Function 1: Read in a file to an array
void getData(int i, int j)
{
	ifstream input;					// ifstream
	input.open("num.txt");			// open text file containing the information

	for (int i = 0; i < col; i++)	//nested for loop to assemble .txt into a 2D Array
	{
		for (int j = 0; j < row; j++)
		{
			input >> array2D[i][j];
			cout << array2D[i][j];
			cout << " ";
		}

	}

}

int main()
{
	//Call functions 
	getData(array2D);

	system("pause");
	return 0;
}

[g3n0m3]

you dont need any parameters for rowsum

just run the loops like you did in getData but insead of input and output add to a variable the number from array2D[i][j] and in another variable add the number from array2D[j][i] for each iteration of j for

so after you done with the second loop you output both variable divided by the number of rows or colums accordingly

[Thomas1965]

I would do it like this:

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

using namespace std;

const int ROW_COUNT = 15;
const int COL_COUNT = 15;

//PROTOTYPES:
void getData(int data[ROW_COUNT][COL_COUNT]);
int  rowSum(int data[ROW_COUNT][COL_COUNT], int row);
int  colSum(int data[ROW_COUNT][COL_COUNT], int col);
int  colAverage(int data[ROW_COUNT][COL_COUNT]);
int  rowAverage(int data[ROW_COUNT][COL_COUNT]);

int main()
{
  int data[ROW_COUNT][COL_COUNT];

	getData(data);

	system("pause");
	return 0;
}



void getData(int data[ROW_COUNT][COL_COUNT])
{
	ifstream input("num.txt");
	
  if (!input)
  {
    cerr << "\aERROR opening file - abort";
    exit(EXIT_FAILURE);
  }

	for (int row = 0; row < ROW_COUNT; row++)	//nested for loop to assemble .txt into a 2D Array
	{
		for (int col = 0; col < COL_COUNT; col++)
		{
			input >> data[row][col];
		}
	}
}

int  rowSum(int data[ROW_COUNT][COL_COUNT], int row)
{
  // TODO - place your code here
}
int  colSum(int data[ROW_COUNT][COL_COUNT], int col)
{
  // TODO - place your code here
}
int  colAverage(int data[ROW_COUNT][COL_COUNT])
{
  // TODO - place your code here
}
int  rowAverage(int data[ROW_COUNT][COL_COUNT])
{
  // TODO - place your code here
}