Variable Not Intialized?

[MisterTams]

Quick question. Can anyone explain to me how my variable (feet) is not initialized?

#include <iostream>
#include <string>
using namespace std;

void Feet2Inches (double feet)
{

double FeetInches;

cout << "Please type units in Feet." << endl;
cout << "Feet: " << endl;
cin >> feet;

FeetInches = feet * 12;
cout << feet << " feet = " << FeetInches << " inches." << endl;
}

int main ()
{

	int conversion;
	double feet, inches, meters, kilometers, pounds, ounces;

	cout << "Welcome to the unit converter!" << endl;
	cout << "Here is the list of units and conversions you can select to calculate the conversion." << endl;
	
	cout << "List of Conversions!" << endl;
	cout << "_____________________________________" << endl;
	cout << "1. Feet to Inches" << endl;
	cout << "2. Inches to Feet" << endl;
	cout << "3. Meters to Kilometers" << endl;
	cout << "4. Kilometers to Meters" << endl;
	cout << "5. Pounds to Ounces" << endl;
	cout << "6. Ounces to Pounds" << endl;

	cout << "Please select a conversion from the list (1-6)" << endl;
	cin >> conversion;

	while (conversion < 1 || conversion > 6)
	{
		std::cout << "Please know that you have selected an invalid conversion." << endl;
		cout << "Select a conversion from the list that is numbered (1-6)." << endl;
		cout << "Enter the number now..." << endl;
		cin >> conversion;
	}

	cout << "Okay!\n" << endl;

	switch (conversion)
	{
	case 1: 
	cout << "You selected (Feet to Inches)" << endl;
	Feet2Inches (feet);
	break;
	case 2:
	cout << "You selected (Inches to Feet)" << endl;
	break;
	case 3: 
	cout << "You selected (Meters to Kilometers)" << endl;
	break;
	case 4:
	cout << "You selected (Kilometers to Meters)" << endl;
	break;
	case 5:
	cout << "You selected (Pounds to Ounces)" << endl;
	break;
	case 6:
	cout << "You selected (Ounces to Pounds)" << endl;
	break;
	}


system("pause");
return 0;
}

[jlb]

In main(), where did you initialize (assign a value) to feet?

Since you passed the variable by value to the function, the function doesn't count.

[Too Explosive]

On line 53 you callFeet2Inches(feet)before this however feet is never given a value.

I believe it would better suit your needs if instead you defined the function without parameters, i.e.void Feet2Inches(void), then simply call it as Feet2Inches();.

[MisterTams]

Yeah Too Explosive,

That makes alot of sense. I've been working alot recently with Arrays and I guess working with them made me get into the habit of using parameters. I totally see what you mean. It definitely would be best to go the simple route and do without parameters in the function(s).

Thanks

[ne555]

it would be better to make actual use of the parameters.
the i/o code may be in main, and the other functions would only perform calculations.

As it is, your `Feet2Inches()' function is quite useless. There are more interesting things to do than to print to screen.

[MisterTams]

ne555,

Could you propose me an example or suggestion?

[ne555]

double Feet2Inches (double feet){
   return feet * 12;
}

int main(){
  //...
	switch (conversion)
	{
	case 1: 
		cout << "You selected (Feet to Inches)" << endl;
		cout << "Please type units in Feet." << endl;
		cout << "Feet: " << endl;
		cin >> feet;
		cout << feet << " feet = "
			<< Feet2Inches (feet)<< " inches." << endl;
		break;
	//...
}

you may also capture the returned value into a variable, for later use.