Double, approximation of Pi Learn programming C# Sharp

Lesson:

Basic Data Types


Exercise:

Double, approximation of Pi 15


Objetive:

Create a program to calculate an approximation for PI using the expression:

pi/4 = 1/1 - 1/3 + 1/5 -1/7 + 1/9 - 1/11 + 1/13 ...

The user will indicate how many terms must be used, and the program will display all the results until that amount of terms.


Code:

using System;
public class exercise66
{
    public static void Main()
    {
        int terms;
        double result = 0;

        Console.WriteLine("PI estimator!");
        Console.Write("Enter the amount of terms to test: ");
        terms = Convert.ToInt32(Console.ReadLine());

        for (int i = 1; i <= terms; i++)
        {
            int divisor = 2 * i - 1;
            if (i % 2 == 1)
                result += 1.0f / divisor;
            else
                result -= 1.0f / divisor;

            Console.WriteLine("To term {0}: {1}",
              i, 4 * result);
        }
    }
}