Is there anyway I can insert Pi into an equation using C ++ without having to write out the whole number?

Printable View

- 09-20-2001Nate2430Pi
Is there anyway I can insert Pi into an equation using C ++ without having to write out the whole number?

- 09-20-2001Unregistered
does this help?????

/**************************

to use this program please

leave my comments box

untouched, otherwise use as

you will.

this program displays the

use (and definition) of PI

written by

MICHAEL MCGUIRE 20/09/01

**************************/

#include<iostream.h>

#include<math.h>

void main()

{

float length;

float width;

float diameter;

float area;

float num;

double pi = atan(1) * 4;//define pi

cout<<"AREA CALCULATOR\n\n\n\n";//title

cout<<"select a shape from below\n";

cout<<"1:- rectangle\n";

cout<<"2:- circle\n";

cout<<"3:- triangle\n";

cout<<"\nenter a number and then press enter\n";

cin>>num;

if (num == 1){//if 1 is entered do this

cout<<"\nenter the length of the rectangle : ";

cin>>length;

cout<<"\nenter the width of the rectangle : ";

cin>>width;

area=(length * width);

cout<<"\n\nthe area of your rectangle is :"<<area;

cout<<endl;

}

else if (num == 2){//or if 2 is entered do this

cout<<"\nenter the diameter of the circle : ";

cin>>diameter;

area=(pi * diameter);////

cout<<"\n\nthe area of your circle is : "<<area;

cout<<endl;

}

else if (num == 3){//or if 3 is entered do this

cout<<"\nenter the length of the triangle : ";

cin>>length;

cout<<"\nenter the width of the triangle : ";

cin>>width;

area=(length*width)/2;

cout<<"\n\nthe area of your triangle is : "<<area;

cout<<endl;

}

//if none of the above are enterd do this (error statement!!!)

else cout<<" ********** WRONG NUMBER ENTERED ***********\n\n\n\n";

//maybe add a loop statement to the program

//in case the user isn't finished

}//end of program - 09-20-2001Nate2430
Thank you. It works.

- 09-20-2001Govtcheez
or you could just say

const double PI = 3.14159265359

Is that that difficult?