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