DaniWeb Forum Index > Software Development > C++

assignment operator for a 3d array

Please support our C++ advertiser: Programming Forums - DaniWeb Sister Site

•

Join Date: Mar 2005

Posts: 91

Reputation: tyczj is an unknown quantity at this point

Solved Threads: 1

tyczj

Offline

Junior Poster in Training

assignment operator for a 3d array

Feb 26th, 2006

im not sure how to write an assignment operator for a 3d array this is what i have bit i know its wrong

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
Cells& Cells::operator= (const Cells& cells)
{
	resetSize(cells.DEPTH, cells.ROW, cells.COL);
 
	for(int d=0; d<DEPTH; d++)
		for(int r=0; r<ROW; r++)
			array[d][r] = **this
			for(int c=0; c<COL; c++)
				array[d][r][c] = cells.array[d][r][c];
			return *this;
 
}
Cells& Cells::operator= (const Cells& cells)
{
	resetSize(cells.DEPTH, cells.ROW, cells.COL);

	for(int d=0; d<DEPTH; d++)
		for(int r=0; r<ROW; r++)
			array[d][r] = **this
			for(int c=0; c<COL; c++)
				array[d][r][c] = cells.array[d][r][c];
			return *this;
			
}

am i at least close on what im suppose to do??

•

Join Date: Aug 2005

Posts: 15,662

Reputation: Ancient Dragon has a reputation beyond repute

Solved Threads: 1502

Ancient Dragon Ancient Dragon is offline

Offline

Still Learning

Re: assignment operator for a 3d array

Feb 26th, 2006

use braces to encose blocks of code. The below may or may not be what you intended.

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
for(int d=0; d<DEPTH; d++)
{
		for(int r=0; r<ROW; r++)
                {
			array[d][r] = **this
			for(int c=0; c<COL; c++)
                        {
				array[d][r][c] = cells.array[d][r][c];
                         }
			return *this;
                }
}
for(int d=0; d<DEPTH; d++)
{
		for(int r=0; r<ROW; r++)
                {
			array[d][r] = **this
			for(int c=0; c<COL; c++)
                        {
				array[d][r][c] = cells.array[d][r][c];
                         }
			return *this;
                }
}

•

Join Date: Mar 2005

Posts: 91

Reputation: tyczj is an unknown quantity at this point

Solved Threads: 1

tyczj

Offline

Junior Poster in Training

Re: assignment operator for a 3d array

Feb 27th, 2006

no i still get errors with brackets

with brackets i get:
error C2100: illegal indirection.

error C2679: binary '=' : no operator defined which takes a right-hand operand of type 'class Darray' (or there is no acceptable conversion).

without i get:
error C2100: illegal indirection.

error C2679: binary '=' : no operator defined which takes a right-hand operand of type 'class Darray' (or there is no acceptable conversion)

error C2065: 'r' : undeclared identifier.

they point to where it says "array[d][r] = **this"

•

Join Date: Jun 2005

Posts: 1,496

Reputation: WolfPack has a spectacular aura about

Solved Threads: 104

WolfPack

Offline

Mentally Challenged Mod.

Re: assignment operator for a 3d array

Feb 27th, 2006

Try this.

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
Cells& Cells::operator= (const Cells& cells)
{
	resetSize(cells.DEPTH, cells.ROW, cells.COL);
	for(int d=0; d<DEPTH; d++)
        {
		for(int r=0; r<ROW; r++)
                {
			for(int c=0; c<COL; c++)
                        {
				array[d][r][c] = cells.array[d][r][c];
                        }
                 }
         }
         return this;		
}
Cells& Cells::operator= (const Cells& cells)
{
	resetSize(cells.DEPTH, cells.ROW, cells.COL);
	for(int d=0; d<DEPTH; d++)
        {
		for(int r=0; r<ROW; r++)
                {
			for(int c=0; c<COL; c++)
                        {
				array[d][r][c] = cells.array[d][r][c];
                        }
                 }
         }
         return this;		
}

•

Join Date: Aug 2005

Posts: 15,662

Reputation: Ancient Dragon has a reputation beyond repute

Solved Threads: 1502

Ancient Dragon Ancient Dragon is offline

Offline

Still Learning

Re: assignment operator for a 3d array

Feb 27th, 2006

**this is an illegal dereference of the "this" pointer in c++. What is the intent of that assignment?

•

Join Date: Mar 2005

Posts: 91

Reputation: tyczj is an unknown quantity at this point

Solved Threads: 1

tyczj

Offline

Junior Poster in Training

Re: assignment operator for a 3d array

Feb 27th, 2006

•

Originally Posted by Ancient Dragon

**this is an illegal dereference of the "this" pointer in c++. What is the intent of that assignment?

i thought i needed it to get a pointer of a 2d array then another pointer for the 3d array to make dynamic.

•

Join Date: Aug 2005

Posts: 15,662

Reputation: Ancient Dragon has a reputation beyond repute

Solved Threads: 1502

Ancient Dragon Ancient Dragon is offline

Offline

Still Learning

Re: assignment operator for a 3d array

Feb 27th, 2006

the this pointer is not a pointer to an array but a pointer to a specific instance of the entire class. you are mis-using the this pointer. You need to post more code in order for anyone to show you how to do whatever it is you want to do.

•

Join Date: Mar 2005

Posts: 91

Reputation: tyczj is an unknown quantity at this point

Solved Threads: 1

tyczj

Offline

Junior Poster in Training

Re: assignment operator for a 3d array

Feb 27th, 2006

here is my whole code but i think i figured it out though. the code has what i changed in it. and i see what your saying now though

 Help with Code Tags 
 C++ Syntax (Toggle Plain Text) 
#include <iostream>
#include "ArrowKeys.h"
using namespace std;
 
 
class Darray{
private:
		int DEPTH,
			  ROW,
			  COL;
		int*** array;
 
public:
 
	Darray();
	Darray(int depth, int row, int col);
	~Darray();
	Darray(const Darray& darray);						//copy constructor
	Darray& Darray::operator= (const Darray& darray);	//assignment operator
 
	void getDimensions(int DEPTH, int ROW, int COL);
	void destroy();
	void create();
	void init();
	void resetSize(int depth, int row, int col);
 
 
};
 
Darray::Darray()
{
	DEPTH=0;
	ROW=0;
	COL=0;
	array=NULL;
}
 
void Darray::create()
{
	array = new int** [DEPTH];
	for(int d=0; d<DEPTH; d++)
		*(array+d) = new int* [ROW];
	for (int r=0; r<ROW; r++)
		*(*(array+d)+r) = new int [COL];
}
 
Darray::Darray(int depth, int row, int col)
{
	DEPTH = depth;
	ROW = row;
	COL = col;
	create();
 
}
 
Darray::~Darray()
{
	destroy();
}
 
Darray::Darray(const Darray& darray)
{
	DEPTH = darray.DEPTH;
	ROW = darray.ROW;
	COL = darray.COL;
	create();
 
	for(int d=0; d<DEPTH; d++)
		for(int r=0; r<ROW; r++)
			for(int c=0; c<COL; c++)
				array[d][r][c] = darray.array[d][r][c];
}
 
Darray& Darray::operator= (const Darray& darray)
{
	resetSize(darray.DEPTH, darray.ROW, darray.COL);
 
	for(int d=0; d<DEPTH; d++)
		for(int r=0; r<ROW; r++)
			for(int c=0; c<COL; c++)
				array[d][r][c] = darray.array[d][r][c];
 
			return *this;	
}
 
void Darray::destroy()
{
	 for (int d=0; d<DEPTH; d++)
	 {
		 for(int r=0; r<ROW; r++)
			 delete [] *(*(array+d)+r);
		 delete [] *(array+d);
	 }
	 delete [] array;
 }
 
void Darray::init()
{
	for(int d=0; d<DEPTH; d++)
		for(int r=0; r<ROW; r++)
			for(int c=0; c<COL; c++)
				array[d][r][c] = 0;
}
 
void Darray::getDimensions(int DEPTH, int ROW, int COL)
{
	cout << "Enter the grid dimensions: " << endl;
	cin >> DEPTH >> ROW >> COL;
 
	cout << "The Depth is: " << DEPTH << "  The Row is: " << ROW
		<< "  The Columns is: " << COL << endl;
}
 
void Darray::resetSize(int depth, int row, int col)
{
	destroy();
	DEPTH=depth;
	ROW=row;
	COL=col;
	create();
	init();
}
#include <iostream>
#include "ArrowKeys.h"
using namespace std;


class Darray{
private:
		int DEPTH,
			  ROW,
			  COL;
		int*** array;

public:
	
	Darray();
	Darray(int depth, int row, int col);
	~Darray();
	Darray(const Darray& darray);						//copy constructor
	Darray& Darray::operator= (const Darray& darray);	//assignment operator

	void getDimensions(int DEPTH, int ROW, int COL);
	void destroy();
	void create();
	void init();
	void resetSize(int depth, int row, int col);


};

Darray::Darray()
{
	DEPTH=0;
	ROW=0;
	COL=0;
	array=NULL;
}

void Darray::create()
{
	array = new int** [DEPTH];
	for(int d=0; d<DEPTH; d++)
		*(array+d) = new int* [ROW];
	for (int r=0; r<ROW; r++)
		*(*(array+d)+r) = new int [COL];
}

Darray::Darray(int depth, int row, int col)
{
	DEPTH = depth;
	ROW = row;
	COL = col;
	create();

}

Darray::~Darray()
{
	destroy();
}

Darray::Darray(const Darray& darray)
{
	DEPTH = darray.DEPTH;
	ROW = darray.ROW;
	COL = darray.COL;
	create();

	for(int d=0; d<DEPTH; d++)
		for(int r=0; r<ROW; r++)
			for(int c=0; c<COL; c++)
				array[d][r][c] = darray.array[d][r][c];
}

Darray& Darray::operator= (const Darray& darray)
{
	resetSize(darray.DEPTH, darray.ROW, darray.COL);

	for(int d=0; d<DEPTH; d++)
		for(int r=0; r<ROW; r++)
			for(int c=0; c<COL; c++)
				array[d][r][c] = darray.array[d][r][c];
			
			return *this;	
}

void Darray::destroy()
{
	 for (int d=0; d<DEPTH; d++)
	 {
		 for(int r=0; r<ROW; r++)
			 delete [] *(*(array+d)+r);
		 delete [] *(array+d);
	 }
	 delete [] array;
 }

void Darray::init()
{
	for(int d=0; d<DEPTH; d++)
		for(int r=0; r<ROW; r++)
			for(int c=0; c<COL; c++)
				array[d][r][c] = 0;
}

void Darray::getDimensions(int DEPTH, int ROW, int COL)
{
	cout << "Enter the grid dimensions: " << endl;
	cin >> DEPTH >> ROW >> COL;

	cout << "The Depth is: " << DEPTH << "  The Row is: " << ROW
		<< "  The Columns is: " << COL << endl;
}

void Darray::resetSize(int depth, int row, int col)
{
	destroy();
	DEPTH=depth;
	ROW=row;
	COL=col;
	create();
	init();
}