Accessing elements from previous object in successive object read

[mike99]

Hi,
Just wondering about how to access elements off an object from previous object of the same type,

#include "stdafx.h"
#include <iostream>
#include <conio.h>
using namespace std;

class DataMat
{
public:
	double element[3][4];
public:
	explicit DataMat(void);
	virtual ~DataMat(void);
	void InitializeElements(void);
	void ShowElements(void);
	void GetAverage(void);
};


DataMat::DataMat(void)	
{
	 for(int i=0;i<3;i++)
	{
	  for(int j=0;j<4;j++)
	  {
	     element[i][j]=0;
	  }	  
	}
}

DataMat::~DataMat(void)
{
   
}

void DataMat::InitializeElements(void)
{
    for(int i=0;i<3;i++)
	{
	  for(int j=0;j<4;j++)
	  {
	     element[i][j]=(int)(rand());
	  }	  
	}

}

void DataMat::ShowElements(void)
{
	this->InitializeElements();

	      for(int i=0;i<3;i++)
			{
			  for(int j=0;j<4;j++)
			  {
				  cout<<"   "<<this->element[i][j];
			  }	 
			  cout<<endl;
			}

}
int _tmain(int argc, _TCHAR* argv[])
{
	double buff[3][4];
	DataMat temp,temp_prev;
		while(_getch()!='q')
		{
			  temp.ShowElements();
			  temp_prev=temp;
			  cout<<endl;
			  cout<<"#"<<endl;
			  temp_prev.ShowElements();
			  cout<<endl<<endl;
		}
		 // _getch();
	return 0;
}

I was expecting temp_prev to show same elements as temp after being assigned by temp.

I must be missing some thing too basic?I have to take running average of 3 elements coloumn wise, have been struck with this.

Thank you

[cire]

ShowElements calls InitializeElements which assigns random numbers to the internal array. ShowElements will never show the elements that exist when the function is called.

[Dy7SLyTq]

it would, but then when you have temp_prev show its elements, its gonna call initializeelements which is gonna over write all of the elements with the rand() call

[mike99]

But how to over come this,I need to access few elements from the previous instantation. Any pointers in that direction?

[Dy7SLyTq]

overload the ='s operator and have each class have a bool variable that is set to true when you do that and then when it comes to initializeelements run it only if the bool variable is set to false

[Daleth]

Take out line 49.

DataMat temp, temp_prev;
temp.InitializeElements();

[mike99]

@Daleth
Accurate, Thank you