Added functions to get a certain number of primes

Algorithms.ts

@@ -1,10 +1,10 @@
 //typescriptClasses/Algorithms.ts
 //Matthew Ellison
 // Created: 10-19-20
-//Modified: 10-19-20
+//Modified: 03-10-21
 //This class holds many algorithms that I have found it useful to keep around
 /*
-Copyright (C) 2020  Matthew Ellison
+Copyright (C) 2021  Matthew Ellison
 
 	This program is free software: you can redistribute it and/or modify
 	it under the terms of the GNU Lesser General Public License as published by
@@ -218,6 +218,107 @@ export function getPrimesBig(goalNumber: bigint): bigint[]{
 	return primes;
 }
 
+export function getNumPrimes(numberOfPrimes: number): number[]{
+	let primes: number[] = [];	//Holds the prime numbers
+	let foundFactor: boolean = false;	//A flag for whether a factor of the current number has been found
+
+	//If the number is 0 or negative return an empty list
+	if(numberOfPrimes <= 1){
+		return primes;
+	}
+	//Otherwise the number is at least 2, so 2 should be added to the list
+	else{
+		primes.push(2);
+	}
+
+	//We can now start at 3 and skip all even number, because they cannot be prime
+	for(let possiblePrime: number = 3;primes.length < numberOfPrimes;possiblePrime += 2){
+		//Check all the current primes, up to sqrt(possiblePrime), to see if there is a divisor
+		let topPossibleFactor: number = Math.ceil(Math.sqrt(possiblePrime));
+		//We can safely assume that there will be at least 1 element in the primes list because of 2 being added by default
+		for(let primesCnt: number = 0;primes[primesCnt] <= topPossibleFactor;){
+			if((possiblePrime % primes[primesCnt]) == 0){
+				foundFactor = true;
+				break;
+			}
+			else{
+				++primesCnt;
+			}
+			//Check if the index has gone out of bounds
+			if(primesCnt >= primes.length){
+				break;
+			}
+		}
+
+		//If you didn't find a factor then the current number must be prime
+		if(!foundFactor){
+			primes.push(possiblePrime);
+		}
+		else{
+			foundFactor = false;
+		}
+	}
+
+	//Sort the list before returning it
+	primes = primes.sort((n1, n2) => n1 - n2);
+	return primes;
+}
+export function getNumPrimesBig(numberOfPrimes: bigint): bigint[]{
+	let primes: bigint[] = [];	//Holds the prime numbers
+	let foundFactor: boolean = false;	//A flag for whether a factor of the current number has been found
+
+	//If the number is 0 or negative return an empty list
+	if(numberOfPrimes <= 1){
+		return primes;
+	}
+	//Otherwise the number is at least 2, so 2 should be added to the list
+	else{
+		primes.push(2n);
+	}
+
+	//We can now start at 3 and skip all even number, because theyu cannot be prime
+	for(let possiblePrime: bigint = 3n;primes.length < numberOfPrimes;possiblePrime += 2n){
+		//Check all the current primes, up to sqrt(possiblePrime), to see if there is a divisor
+		let topPossibleFactor: bigint = sqrtBig(possiblePrime);
+		//We can safely assume that ther ewill be at least 1 element in the primes list because of 2 being added by default
+		for(let primesCnt: number = 0;primes[primesCnt] <= topPossibleFactor;){
+			if((possiblePrime % primes[primesCnt]) == 0n){
+				foundFactor = true;
+				break;
+			}
+			else{
+				++primesCnt;
+			}
+			//Check if the index has gone out of bounds
+			if(primesCnt >= primes.length){
+				break;
+			}
+		}
+
+		//If you didn't find a factor then the current number must be prime
+		if(!foundFactor){
+			primes.push(possiblePrime);
+		}
+		else{
+			foundFactor = false;
+		}
+	}
+
+	//Sort the list before returning it
+	primes = primes.sort(function(n1, n2){
+		if(n1 > n2){
+			return 1;
+		}
+		else if(n1 < n2){
+			return -1;
+		}
+		else{
+			return 0;
+		}
+	});
+	return primes;
+}
+
 export function getFactors(goalNumber: number): number[]{
 	//You need to get all the primes that could be factors of this number so you can test them
 	let topPossiblePrime: number = Math.ceil(Math.sqrt(goalNumber));

TestAlgorithms.ts

@@ -1,10 +1,10 @@
 //typescriptClasses/Algorithms.ts
 //Matthew Ellison
 // Created: 10-19-20
-//Modified: 10-19-20
+//Modified: 03-10-21
 //This class holds many algorithms that I have found it useful to keep around
 /*
-Copyright (C) 2020  Matthew Ellison
+Copyright (C) 2021  Matthew Ellison
 
 	This program is free software: you can redistribute it and/or modify
 	it under the terms of the GNU Lesser General Public License as published by
@@ -20,8 +20,9 @@ Copyright (C) 2020  Matthew Ellison
 	along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */
 
+
 import assert = require("assert");
-import { arrayEquals, getAllFib, getAllFibBig, getFactors, getFactorsBig, getPrimes, getPrimesBig } from "./Algorithms";
+import { arrayEquals, getAllFib, getAllFibBig, getFactors, getFactorsBig, getPrimes, getPrimesBig, getNumPrimes, getNumPrimesBig } from "./Algorithms";
 
 
 function testGetAllFib(){
@@ -61,6 +62,22 @@ function testGetPrimes(){
 	console.log("getPrimes passed");
 }
 
+function testGetNumPrimes(){
+	//Test1
+	let correctAnswer = [2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97];
+	let numPrimes = 25;
+	let answer = getNumPrimes(numPrimes);
+	assert.ok(arrayEquals(answer, correctAnswer), "getNumPrimes number failed");
+
+	//Test2
+	let bigCorrectAnswer = [2n, 3n, 5n, 7n, 11n, 13n, 17n, 19n, 23n, 29n, 31n, 37n, 41n, 43n, 47n, 53n, 59n, 61n, 67n, 71n, 73n, 79n, 83n, 89n, 97n];
+	let bigNumPrimes = 25n;
+	let bigAnswer = getNumPrimesBig(bigNumPrimes);
+	assert.ok(arrayEquals(bigAnswer, bigCorrectAnswer), "getNumPrimesBig failed");
+
+	console.log("getNumPrimes passed");
+}
+
 function testGetFactors(){
 	//Test 1
 	let correctAnswer = [2, 2, 5, 5];
@@ -86,4 +103,5 @@ function testGetFactors(){
 //Run all of the tests
 testGetAllFib();
 testGetPrimes();
+testGetNumPrimes();
 testGetFactors();