Thread: Problems with displaying class variables

Whenever I try to display class variables in my program I get weird results that I shouldn't be getting such as "-7.92985e+185" instead of a real number. I'm not sure where the problem is coming from, when the program ran off all functions it worked fine. Any help is appreciated, thanks in advance.

Proto.h

Code:

#ifndef proto_h
#define proto_h

class myArea
{
private:
	double length_c;
	double width_c;
	double height_c;

public:
	void setlw(double length, double width);
	void setheight(double height);
	void setlwh(double length, double width, double height);

	void getlw(double length, double width);
	void getheight(double height);
	void getlwh(double length, double width, double height);

	double findfloorarea(void);
	double findawallarea(void);
	double findvolume(void);

	void show_findfloorarea(void);
	void show_findwallarea(void);
	void show_findvolume(void);
	void show_height(void);
}; 

#endif

myArea.cpp

Code:

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

void myArea::setlw(double length, double width)
{
	if (length_c > 0, width_c > 0)
	{
		length_c = length;
		width_c = width;
	}
}

void myArea::setheight(double height)
{
	if (height_c > 0)
	{
		height_c = height;
	}
}

void myArea::setlwh(double length, double width, double height)
{
	if (length_c > 0, width_c > 0, height_c > 0)
	{
		length_c = length;
		width_c = width;
		height_c = height;
	}
}

void myArea::getlw(double length, double width)
{
	length = length_c;
	width = width_c;
}

void myArea::getheight(double height)
{
	height = height_c;
}

void myArea::getlwh(double length, double width, double height)
{
	length = length_c;
	width = width_c;
	height = height_c;
}

void myArea::show_findfloorarea(void)
{
	cout<<(length_c * width_c)<<endl;
}

void myArea::show_findwallarea(void)
{
	cout<<(length_c * height_c)<<endl;
}

void myArea::show_findvolume(void)
{
	cout<<(length_c * width_c * height_c)<<endl;
}

void myArea::show_height(void)
{
	cout<<height_c<<endl;
}

main.cpp

Code:

#include <iostream>
#include "proto.h"

using namespace std;

void demo(const double & l, const double & w, const double & h);

int main()
{
	demo(4,3,5);
	demo(5,8,12);
	demo(8,3,18);
	demo(6,14,9);
	demo(7,13,2);
	return 0;
}

void demo(const double & l, const double & w, const double & h)
{
	myArea area;
	cout<<"Using functions: 'setlw()','getlw()' and 'show_findfloorarea()', with the parameters "<<l<<", "<<w<<"."<<endl;
	area.setlw(l,w);
	area.getlw(l,w);
	area.show_findfloorarea();
	cout<<"Using functions: 'setheight()','getheight()' and 'show_findwallarea()' with the parameter "<<h<<"."<<endl;
	area.setheight(h);
	area.getheight(h);
	area.show_findwallarea();
	cout<<"Using functions: 'setlwh()','getlwh()' and 'show_findvolume()' with the parameters "<<l<<", "<<w<<", "<<h<<"."<<endl;
	area.setlwh(l,w,h);
	area.getlwh(l,w,h);
	area.show_findvolume();
	cout<<endl;

}

Originally Posted by swoopy

Same problem here:
> if (length_c > 0, width_c > 0)

>void myArea::setheight(double height)
>{
> if (height_c > 0)

This should be:
if (height > 0)

Yes, that fixed it. Its obvious now, it was testing the global variable when it should have been checking the local one. Thank you.