diff --git a/Maths/PiNilakantha.java b/Maths/PiNilakantha.java new file mode 100644 index 000000000..3ff8550ac --- /dev/null +++ b/Maths/PiNilakantha.java @@ -0,0 +1,46 @@ +package Maths; + +public class PiNilakantha { + + // Calculates Pi using Nilakantha's infinite series + // Method 2 in the following link explains the algorithm + //https://en.scratch-wiki.info/wiki/Calculating_Pi + + + public static void main(String[] args) { + assert calculatePi(0) == 3.0; + assert calculatePi(10) > 3.0; + assert calculatePi(100) < 4.0; + + System.out.println(calculatePi(500)); + } + + + /** + * + * @param iterations number of times the infinite series gets repeated + * Pi get more accurate the higher the value of iterations is + * Values from 0 up to 500 are allowed since double precision is not sufficient + * for more than about 500 repetitions of this algorithm + * @return the pi value of the calculation with a precision of x iteration + */ + public static double calculatePi(int iterations) { + if (iterations < 0 || iterations > 500) { + throw new IllegalArgumentException("Please input Integer Number between 0 and 500"); + } + + double pi = 3; + int divCounter = 2; + + for (int i = 0; i < iterations; i++) { + + if (i % 2 == 0) + pi = pi + 4.0 / (divCounter * (divCounter + 1) * (divCounter + 2)); + else + pi = pi - 4.0 / (divCounter * (divCounter + 1) * (divCounter + 2)); + + divCounter += 2; + } + return pi; + } +}