From e112434dee038b4605fe7bbd4e3e7b5b5e322073 Mon Sep 17 00:00:00 2001
From: Ephraim Atta-Duncan <55143799+dephraiim@users.noreply.github.com>
Date: Sun, 11 Oct 2020 19:47:49 +0000
Subject: [PATCH] Add tests to Math (#423)

* Add prettier config

* test: add test to check for absolute function

* chore: es5 to es6

* test: add test to check mean function

* test: add test for sum of digit

* test: add test for factorial

* test: add test for fibonnaci

* test: add test for find HCF

* test: add test for lcm

* test: add gridget test

* test: add test for mean square error

* test: add test for modular binary exponentiation

* test: add tests for palindrome

* test: add test for pascals triangle

* test: add tests for polynomial

* test: add tests for prime check

* test: add tests for reverse polish notation

* test: add tests for sieve of eratosthenes

* test: add tests for pi estimation monte carlo method

* chore: move tests to test folder

* chore: fix standardjs errors
---
 .prettierrc                                   | 15 ++++++
 Maths/Abs.js                                  |  6 +--
 Maths/AverageMean.js                          |  8 ++-
 Maths/{digitSum.js => DigitSum.js}            |  8 ++-
 Maths/Factorial.js                            | 19 +++----
 Maths/Fibonacci.js                            | 18 ++-----
 Maths/FindHcf.js                              |  5 +-
 Maths/FindLcm.js                              | 25 ++++++----
 Maths/GridGet.js                              | 11 ++---
 Maths/MeanSquareError.js                      |  7 +--
 Maths/ModularBinaryExponentiationRecursive.js | 11 +----
 Maths/Palindrome.js                           |  9 ++--
 Maths/PascalTriangle.js                       | 27 +++++-----
 Maths/PiApproximationMonteCarlo.js            |  8 +--
 Maths/Polynomial.js                           | 49 ++++++-------------
 Maths/PrimeCheck.js                           | 14 ++----
 Maths/ReversePolishNotation.js                |  8 ++-
 Maths/SieveOfEratosthenes.js                  | 22 +++------
 Maths/test/Abs.test.js                        | 13 +++++
 Maths/test/AverageMean.test.js                | 11 +++++
 Maths/test/DigitSum.test.js                   | 11 +++++
 Maths/test/Factorial.test.js                  | 35 +++++++++++++
 Maths/test/Fibonacci.test.js                  | 30 ++++++++++++
 Maths/test/FindHcf.test.js                    | 20 ++++++++
 Maths/test/FindLcm.test.js                    | 20 ++++++++
 Maths/test/GridGet.test.js                    | 16 ++++++
 Maths/test/MeanSquareError.test.js            | 21 ++++++++
 ...dularBinaryExponentiationRecursive.test.js |  7 +++
 Maths/test/Palindrome.test.js                 | 16 ++++++
 Maths/test/PascalTriangle.test.js             | 20 ++++++++
 Maths/test/PiApproximationMonteCarlo.test.js  |  9 ++++
 Maths/test/Polynomial.test.js                 | 37 ++++++++++++++
 Maths/test/PrimeCheck.test.js                 | 14 ++++++
 Maths/test/ReversePolishNotation.test.js      | 11 +++++
 Maths/test/SieveOfEratosthenes.test.js        | 14 ++++++
 String/PatternMatching.js                     |  1 -
 String/{ => test}/CheckAnagram.test.js        |  4 +-
 String/{ => test}/CheckPalindrome.test.js     |  2 +-
 String/{ => test}/PatternMatching.test.js     |  6 ++-
 String/{ => test}/ReverseString.test.js       |  2 +-
 String/{ => test}/ReverseWords.test.js        |  2 +-
 41 files changed, 420 insertions(+), 172 deletions(-)
 create mode 100644 .prettierrc
 rename Maths/{digitSum.js => DigitSum.js} (70%)
 create mode 100644 Maths/test/Abs.test.js
 create mode 100644 Maths/test/AverageMean.test.js
 create mode 100644 Maths/test/DigitSum.test.js
 create mode 100644 Maths/test/Factorial.test.js
 create mode 100644 Maths/test/Fibonacci.test.js
 create mode 100644 Maths/test/FindHcf.test.js
 create mode 100644 Maths/test/FindLcm.test.js
 create mode 100644 Maths/test/GridGet.test.js
 create mode 100644 Maths/test/MeanSquareError.test.js
 create mode 100644 Maths/test/ModularBinaryExponentiationRecursive.test.js
 create mode 100644 Maths/test/Palindrome.test.js
 create mode 100644 Maths/test/PascalTriangle.test.js
 create mode 100644 Maths/test/PiApproximationMonteCarlo.test.js
 create mode 100644 Maths/test/Polynomial.test.js
 create mode 100644 Maths/test/PrimeCheck.test.js
 create mode 100644 Maths/test/ReversePolishNotation.test.js
 create mode 100644 Maths/test/SieveOfEratosthenes.test.js
 rename String/{ => test}/CheckAnagram.test.js (92%)
 rename String/{ => test}/CheckPalindrome.test.js (90%)
 rename String/{ => test}/PatternMatching.test.js (84%)
 rename String/{ => test}/ReverseString.test.js (98%)
 rename String/{ => test}/ReverseWords.test.js (90%)

diff --git a/.prettierrc b/.prettierrc
new file mode 100644
index 000000000..a85cb7eb8
--- /dev/null
+++ b/.prettierrc
@@ -0,0 +1,15 @@
+{
+  "arrowParens": "always",
+  "bracketSpacing": true,
+  "endOfLine": "lf",
+  "insertPragma": false,
+  "printWidth": 80,
+  "proseWrap": "preserve",
+  "quoteProps": "as-needed",
+  "requirePragma": false,
+  "semi": false,
+  "singleQuote": true,
+  "tabWidth": 2,
+  "trailingComma": "none",
+  "useTabs": false
+}
diff --git a/Maths/Abs.js b/Maths/Abs.js
index 454e4073a..4caa783ff 100644
--- a/Maths/Abs.js
+++ b/Maths/Abs.js
@@ -11,7 +11,7 @@
         https://en.wikipedia.org/wiki/Absolute_value
 */
 
-function absVal (num) {
+const absVal = (num) => {
   // Find absolute value of `num`.
   'use strict'
   if (num < 0) {
@@ -21,6 +21,4 @@ function absVal (num) {
   return num
 }
 
-// Run `abs` function to find absolute value of two numbers.
-console.log('The absolute value of -34 is ' + absVal(-34))
-console.log('The absolute value of 34 is ' + absVal(34))
+export { absVal }
diff --git a/Maths/AverageMean.js b/Maths/AverageMean.js
index 28f96d53e..43f3f8ca0 100644
--- a/Maths/AverageMean.js
+++ b/Maths/AverageMean.js
@@ -14,8 +14,7 @@
 
 const mean = (nums) => {
   // This is a function returns average/mean of array
-  var sum = 0
-  var avg
+  let sum = 0
 
   // This loop sums all values in the 'nums' array using forEach loop
   nums.forEach(function (current) {
@@ -23,9 +22,8 @@ const mean = (nums) => {
   })
 
   // Divide sum by the length of the 'nums' array.
-  avg = sum / nums.length
+  const avg = sum / nums.length
   return avg
 }
 
-// Run `mean` Function to find average of a list of numbers.
-console.log(mean([2, 4, 6, 8, 20, 50, 70]))
+export { mean }
diff --git a/Maths/digitSum.js b/Maths/DigitSum.js
similarity index 70%
rename from Maths/digitSum.js
rename to Maths/DigitSum.js
index 3f08cf807..792915d60 100644
--- a/Maths/digitSum.js
+++ b/Maths/DigitSum.js
@@ -1,18 +1,16 @@
 // program to find sum of digits of a number
 
 // function which would calculate sum and return it
-function digitSum (num) {
+const digitSum = (num) => {
   // sum will store sum of digits of a number
   let sum = 0
   // while will run untill num become 0
   while (num) {
-    sum += (num % 10)
+    sum += num % 10
     num = parseInt(num / 10)
   }
 
   return sum
 }
 
-// assigning number
-const num = 12345
-console.log(digitSum(num))
+export { digitSum }
diff --git a/Maths/Factorial.js b/Maths/Factorial.js
index c13878d90..04d9ef08c 100644
--- a/Maths/Factorial.js
+++ b/Maths/Factorial.js
@@ -13,10 +13,10 @@
 
 'use strict'
 
-function calcRange (num) {
+const calcRange = (num) => {
   // Generate a range of numbers from 1 to `num`.
-  var i = 1
-  var range = []
+  let i = 1
+  const range = []
   while (i <= num) {
     range.push(i)
     i += 1
@@ -24,9 +24,9 @@ function calcRange (num) {
   return range
 }
 
-function calcFactorial (num) {
-  var factorial
-  var range = calcRange(num)
+const calcFactorial = (num) => {
+  let factorial
+  const range = calcRange(num)
 
   // Check if the number is negative, positive, null, undefined, or zero
   if (num < 0) {
@@ -43,11 +43,8 @@ function calcFactorial (num) {
     range.forEach(function (i) {
       factorial = factorial * i
     })
-    return 'The factorial of ' + num + ' is ' + factorial
+    return `The factorial of ${num} is ${factorial}`
   }
 }
 
-// Run `factorial` Function to find average of a list of numbers.
-
-var num = console.log('Enter a number: ')
-console.log(calcFactorial(num))
+export { calcFactorial }
diff --git a/Maths/Fibonacci.js b/Maths/Fibonacci.js
index 9a4361781..3a8f83381 100644
--- a/Maths/Fibonacci.js
+++ b/Maths/Fibonacci.js
@@ -66,18 +66,10 @@ const FibonacciDpWithoutRecursion = (number) => {
   for (var i = 2; i < number; ++i) {
     table.push(table[i - 1] + table[i - 2])
   }
-  return (table)
+  return table
 }
 
-// testing
-
-console.log(FibonacciIterative(5))
-// Output: [ 1, 1, 2, 3, 5 ]
-console.log(FibonacciRecursive(5))
-// Output: [ 1, 1, 2, 3, 5 ]
-
-console.log(FibonacciRecursiveDP(5))
-// Output: 5
-
-console.log(FibonacciDpWithoutRecursion(5))
-// Output: [ 1, 1, 2, 3, 5 ]
+export { FibonacciDpWithoutRecursion }
+export { FibonacciIterative }
+export { FibonacciRecursive }
+export { FibonacciRecursiveDP }
diff --git a/Maths/FindHcf.js b/Maths/FindHcf.js
index f6b696219..19105b5aa 100644
--- a/Maths/FindHcf.js
+++ b/Maths/FindHcf.js
@@ -4,7 +4,7 @@
         https://en.wikipedia.org/wiki/Greatest_common_divisor
  */
 
-function findHCF (x, y) {
+const findHCF = (x, y) => {
   // If the input numbers are less than 1 return an error message.
   if (x < 1 || y < 1) {
     return 'Please enter values greater than zero.'
@@ -27,4 +27,5 @@ function findHCF (x, y) {
   // When the while loop finishes the minimum of x and y is the HCF.
   return Math.min(x, y)
 }
-console.log(findHCF(27, 36))
+
+export { findHCF }
diff --git a/Maths/FindLcm.js b/Maths/FindLcm.js
index 60470e37e..0d09a7aff 100644
--- a/Maths/FindLcm.js
+++ b/Maths/FindLcm.js
@@ -12,9 +12,19 @@
 'use strict'
 
 // Find the LCM of two numbers.
-function findLcm (num1, num2) {
-  var maxNum
-  var lcm
+const findLcm = (num1, num2) => {
+  // If the input numbers are less than 1 return an error message.
+  if (num1 < 1 || num2 < 1) {
+    return 'Please enter values greater than zero.'
+  }
+
+  // If the input numbers are not integers return an error message.
+  if (num1 !== Math.round(num1) || num2 !== Math.round(num2)) {
+    return 'Please enter whole numbers.'
+  }
+
+  let maxNum
+  let lcm
   // Check to see whether num1 or num2 is larger.
   if (num1 > num2) {
     maxNum = num1
@@ -24,15 +34,10 @@ function findLcm (num1, num2) {
   lcm = maxNum
 
   while (true) {
-    if ((lcm % num1 === 0) && (lcm % num2 === 0)) {
-      break
-    }
+    if (lcm % num1 === 0 && lcm % num2 === 0) break
     lcm += maxNum
   }
   return lcm
 }
 
-// Run `findLcm` Function
-var num1 = 12
-var num2 = 76
-console.log(findLcm(num1, num2))
+export { findLcm }
diff --git a/Maths/GridGet.js b/Maths/GridGet.js
index 69ae502ef..44ae9a193 100644
--- a/Maths/GridGet.js
+++ b/Maths/GridGet.js
@@ -40,17 +40,14 @@
 */
 
 const gridGetX = (columns, index) => {
-  while ((index + 1) > columns) {
+  while (index + 1 > columns) {
     index = index - columns
   }
-  return (index + 1)
+  return index + 1
 }
 
 const gridGetY = (columns, index) => {
-  return (Math.floor(index / columns)) + 1
+  return Math.floor(index / columns) + 1
 }
 
-console.log(`If a square array has 400 elements,  then the value of x for the 27th element is ${gridGetX(Math.sqrt(400), 27)}`)
-console.log(`If an array has 7 columns and 3 rows,  then the value of x for the 11th element is ${gridGetX(7, 11)}`)
-console.log(`If a square array has 400 elements,  then the value of y for the 27th element is ${gridGetY(Math.sqrt(400), 27)}`)
-console.log(`If an array has 7 columns and 3 rows,  then the value of y for the 11th element is ${gridGetY(7, 11)}`)
+export { gridGetX, gridGetY }
diff --git a/Maths/MeanSquareError.js b/Maths/MeanSquareError.js
index de9dcfd7f..edcd3e699 100644
--- a/Maths/MeanSquareError.js
+++ b/Maths/MeanSquareError.js
@@ -18,9 +18,4 @@ const meanSquaredError = (predicted, expected) => {
   return err / expected.length
 }
 
-// testing
-(() => {
-  console.log(meanSquaredError([1, 2, 3, 4], [1, 2, 3, 4]) === 0)
-  console.log(meanSquaredError([4, 3, 2, 1], [1, 2, 3, 4]) === 5)
-  console.log(meanSquaredError([2, 0, 2, 0], [0, 0, 0, 0]) === 3)
-})()
+export { meanSquaredError }
diff --git a/Maths/ModularBinaryExponentiationRecursive.js b/Maths/ModularBinaryExponentiationRecursive.js
index c30ed5f2a..b8374bd17 100644
--- a/Maths/ModularBinaryExponentiationRecursive.js
+++ b/Maths/ModularBinaryExponentiationRecursive.js
@@ -19,13 +19,4 @@ const modularBinaryExponentiation = (a, n, m) => {
   }
 }
 
-const main = () => {
-  // binary_exponentiation(2, 10, 17)
-  // > 4
-  console.log(modularBinaryExponentiation(2, 10, 17))
-  // binary_exponentiation(3, 9, 12)
-  // > 3
-  console.log(modularBinaryExponentiation(3, 9, 12))
-}
-
-main()
+export { modularBinaryExponentiation }
diff --git a/Maths/Palindrome.js b/Maths/Palindrome.js
index 4abc8d997..34804d34f 100644
--- a/Maths/Palindrome.js
+++ b/Maths/Palindrome.js
@@ -14,7 +14,7 @@
  * @complexity: O(n)
  */
 
-function PalindromeRecursive (string) {
+const PalindromeRecursive = (string) => {
   // Base case
   if (string.length < 2) return true
 
@@ -26,7 +26,7 @@ function PalindromeRecursive (string) {
   return PalindromeRecursive(string.slice(1, string.length - 1))
 }
 
-function PalindromeIterative (string) {
+const PalindromeIterative = (string) => {
   const _string = string
     .toLowerCase()
     .replace(/ /g, '')
@@ -45,7 +45,4 @@ function PalindromeIterative (string) {
   return true
 }
 
-// testing
-
-console.log(PalindromeRecursive('Javascript Community'))
-console.log(PalindromeIterative('mom'))
+export { PalindromeIterative, PalindromeRecursive }
diff --git a/Maths/PascalTriangle.js b/Maths/PascalTriangle.js
index eaf3f2a9e..868e36fca 100644
--- a/Maths/PascalTriangle.js
+++ b/Maths/PascalTriangle.js
@@ -1,6 +1,16 @@
-const numRows = 5
+const addRow = (triangle) => {
+  const previous = triangle[triangle.length - 1]
+  const newRow = [1]
+  for (let i = 0; i < previous.length - 1; i++) {
+    const current = previous[i]
+    const next = previous[i + 1]
+    newRow.push(current + next)
+  }
+  newRow.push(1)
+  return triangle.push(newRow)
+}
 
-var generate = function (numRows) {
+const generate = (numRows) => {
   const triangle = [[1], [1, 1]]
 
   if (numRows === 0) {
@@ -16,16 +26,5 @@ var generate = function (numRows) {
   }
   return triangle
 }
-var addRow = function (triangle) {
-  const previous = triangle[triangle.length - 1]
-  const newRow = [1]
-  for (let i = 0; i < previous.length - 1; i++) {
-    const current = previous[i]
-    const next = previous[i + 1]
-    newRow.push(current + next)
-  }
-  newRow.push(1)
-  return triangle.push(newRow)
-}
 
-generate(numRows)
+export { generate }
diff --git a/Maths/PiApproximationMonteCarlo.js b/Maths/PiApproximationMonteCarlo.js
index a4b3d8b81..be7f754e4 100644
--- a/Maths/PiApproximationMonteCarlo.js
+++ b/Maths/PiApproximationMonteCarlo.js
@@ -1,7 +1,7 @@
 // Wikipedia: https://en.wikipedia.org/wiki/Monte_Carlo_method
 // Video Explaination: https://www.youtube.com/watch?v=ELetCV_wX_c
 
-function piEstimation (iterations = 100000) {
+const piEstimation = (iterations = 100000) => {
   let circleCounter = 0
 
   for (let i = 0; i < iterations; i++) {
@@ -18,8 +18,4 @@ function piEstimation (iterations = 100000) {
   return pi
 }
 
-function main () {
-  console.log(piEstimation())
-}
-
-main()
+export { piEstimation }
diff --git a/Maths/Polynomial.js b/Maths/Polynomial.js
index 740ac3b25..41ec340ee 100644
--- a/Maths/Polynomial.js
+++ b/Maths/Polynomial.js
@@ -1,4 +1,3 @@
-
 /**
  * Polynomials are algebraic expressions consisting of two or more algebraic terms.
  * Terms of a polynomial are:
@@ -20,18 +19,19 @@ class Polynomial {
    * Function to construct the polynomial in terms of x using the coefficientArray
    */
   construct () {
-    this.polynomial = this.coefficientArray.map((coefficient, exponent) => {
-      if (coefficient === 0) {
-        return '0'
-      }
-      if (exponent === 0) {
-        return `(${coefficient})`
-      } else if (exponent === 1) {
-        return `(${coefficient}x)`
-      } else {
-        return `(${coefficient}x^${exponent})`
-      }
-    })
+    this.polynomial = this.coefficientArray
+      .map((coefficient, exponent) => {
+        if (coefficient === 0) {
+          return '0'
+        }
+        if (exponent === 0) {
+          return `(${coefficient})`
+        } else if (exponent === 1) {
+          return `(${coefficient}x)`
+        } else {
+          return `(${coefficient}x^${exponent})`
+        }
+      })
       .filter((x) => {
         if (x !== '0') {
           return x
@@ -55,28 +55,9 @@ class Polynomial {
    */
   evaluate (value) {
     return this.coefficientArray.reduce((result, coefficient, exponent) => {
-      return result + coefficient * (Math.pow(value, exponent))
+      return result + coefficient * Math.pow(value, exponent)
     }, 0)
   }
 }
 
-/**
- * Function to perform tests
- */
-const tests = () => {
-  const polynomialOne = new Polynomial([1, 2, 3, 4])
-  console.log('Test 1: [1,2,3,4]')
-  console.log('Display Polynomial ', polynomialOne.display())
-  // (4x^3) + (3x^2) + (2x) + (1)
-  console.log('Evaluate Polynomial value=2 ', polynomialOne.evaluate(2))
-  // 49
-
-  const polynomialTwo = new Polynomial([5, 0, 0, -4, 3])
-  console.log('Test 2: [5,0,0,-4,3]')
-  console.log('Display Polynomial ', polynomialTwo.display())
-  // (3x^4) + (-4x^3) + (5)
-  console.log('Evaluate Polynomial value=1 ', polynomialTwo.evaluate(1))
-  // 4
-}
-
-tests()
+export { Polynomial }
diff --git a/Maths/PrimeCheck.js b/Maths/PrimeCheck.js
index d46dfab4f..c0f626ce6 100644
--- a/Maths/PrimeCheck.js
+++ b/Maths/PrimeCheck.js
@@ -9,6 +9,9 @@
 const PrimeCheck = (n) => {
   // input: n: int
   // output: boolean
+  if (n === 1) return false
+  if (n === 0) return false
+
   for (let i = 2; i * i <= n; i++) {
     if (n % i === 0) {
       return false
@@ -17,13 +20,4 @@ const PrimeCheck = (n) => {
   return true
 }
 
-const main = () => {
-  // PrimeCheck(1000003)
-  // > true
-  console.log(PrimeCheck(1000003))
-  // PrimeCheck(1000001)
-  // > false
-  console.log(PrimeCheck(1000001))
-}
-
-main()
+export { PrimeCheck }
diff --git a/Maths/ReversePolishNotation.js b/Maths/ReversePolishNotation.js
index ef31300a9..efe6240dc 100644
--- a/Maths/ReversePolishNotation.js
+++ b/Maths/ReversePolishNotation.js
@@ -1,6 +1,6 @@
 // Wikipedia: https://en.wikipedia.org/wiki/Reverse_Polish_notation
 
-function calcRPN (expression) {
+const calcRPN = (expression) => {
   const operators = {
     '+': (a, b) => a + b,
     '-': (a, b) => a - b,
@@ -12,7 +12,7 @@ function calcRPN (expression) {
 
   const stack = []
 
-  tokens.forEach(token => {
+  tokens.forEach((token) => {
     const operator = operators[token]
 
     if (typeof operator === 'function') {
@@ -30,6 +30,4 @@ function calcRPN (expression) {
   return stack.pop()
 }
 
-console.log(calcRPN('2 2 2 * +') === 6)
-console.log(calcRPN('2 2 + 2 *') === 8)
-console.log(calcRPN('6 9 7 + 2 / + 3 *') === 42)
+export { calcRPN }
diff --git a/Maths/SieveOfEratosthenes.js b/Maths/SieveOfEratosthenes.js
index 1e0a2e2b2..9393f58d8 100644
--- a/Maths/SieveOfEratosthenes.js
+++ b/Maths/SieveOfEratosthenes.js
@@ -1,9 +1,9 @@
-function sieveOfEratosthenes (n) {
+const sieveOfEratosthenes = (n) => {
   /*
-     * Calculates prime numbers till a number n
-     * :param n: Number upto which to calculate primes
-     * :return: A boolean list contaning only primes
-     */
+   * Calculates prime numbers till a number n
+   * :param n: Number upto which to calculate primes
+   * :return: A boolean list contaning only primes
+   */
   const primes = new Array(n + 1)
   primes.fill(true) // set all as true initially
   primes[0] = primes[1] = false // Handling case for 0 and 1
@@ -18,14 +18,4 @@ function sieveOfEratosthenes (n) {
   return primes
 }
 
-function main () {
-  const n = 69 // number till where we wish to find primes
-  const primes = sieveOfEratosthenes(n)
-  for (let i = 2; i <= n; i++) {
-    if (primes[i]) {
-      console.log(i)
-    }
-  }
-}
-
-main()
+export { sieveOfEratosthenes }
diff --git a/Maths/test/Abs.test.js b/Maths/test/Abs.test.js
new file mode 100644
index 000000000..116336f85
--- /dev/null
+++ b/Maths/test/Abs.test.js
@@ -0,0 +1,13 @@
+import { absVal } from '../Abs'
+
+describe('absVal', () => {
+  it('should return an absolute value of a negative number', () => {
+    const absOfNegativeNumber = absVal(-34)
+    expect(absOfNegativeNumber).toBe(34)
+  })
+
+  it('should return an absolute value of a positive number', () => {
+    const absOfPositiveNumber = absVal(50)
+    expect(absOfPositiveNumber).toBe(50)
+  })
+})
diff --git a/Maths/test/AverageMean.test.js b/Maths/test/AverageMean.test.js
new file mode 100644
index 000000000..8b3d7bb13
--- /dev/null
+++ b/Maths/test/AverageMean.test.js
@@ -0,0 +1,11 @@
+import { mean } from '../AverageMean'
+
+describe('Tests for average mean', () => {
+  it('should be a function', () => {
+    expect(typeof mean).toEqual('function')
+  })
+  it('should return the mean of an array of numbers', () => {
+    const meanFunction = mean([1, 2, 4, 5])
+    expect(meanFunction).toBe(3)
+  })
+})
diff --git a/Maths/test/DigitSum.test.js b/Maths/test/DigitSum.test.js
new file mode 100644
index 000000000..c9c828be5
--- /dev/null
+++ b/Maths/test/DigitSum.test.js
@@ -0,0 +1,11 @@
+import { digitSum } from '../DigitSum'
+
+describe('digitSum', () => {
+  it('is a function', () => {
+    expect(typeof digitSum).toEqual('function')
+  })
+  it('should return the sum of digits of a given number', () => {
+    const sumOfNumber = digitSum(12345)
+    expect(sumOfNumber).toBe(15)
+  })
+})
diff --git a/Maths/test/Factorial.test.js b/Maths/test/Factorial.test.js
new file mode 100644
index 000000000..bd22ad436
--- /dev/null
+++ b/Maths/test/Factorial.test.js
@@ -0,0 +1,35 @@
+import { calcFactorial } from '../Factorial'
+
+describe('calcFactorial', () => {
+  it('is a function', () => {
+    expect(typeof calcFactorial).toEqual('function')
+  })
+
+  it('should return a statement for value "0"', () => {
+    expect(calcFactorial(0)).toBe('The factorial of 0 is 1.')
+  })
+
+  it('should return a statement for "null" and "undefined"', () => {
+    const nullFactorial = calcFactorial(null)
+    const undefinedFactorial = calcFactorial(undefined)
+
+    expect(nullFactorial).toBe(
+      'Sorry, factorial does not exist for null or undefined numbers.'
+    )
+    expect(undefinedFactorial).toBe(
+      'Sorry, factorial does not exist for null or undefined numbers.'
+    )
+  })
+
+  it('should not support negative numbers', () => {
+    const negativeFactorial = calcFactorial(-5)
+    expect(negativeFactorial).toBe(
+      'Sorry, factorial does not exist for negative numbers.'
+    )
+  })
+
+  it('should return the factorial of a positive number', () => {
+    const positiveFactorial = calcFactorial(3)
+    expect(positiveFactorial).toBe('The factorial of 3 is 6')
+  })
+})
diff --git a/Maths/test/Fibonacci.test.js b/Maths/test/Fibonacci.test.js
new file mode 100644
index 000000000..e5b9376f8
--- /dev/null
+++ b/Maths/test/Fibonacci.test.js
@@ -0,0 +1,30 @@
+import {
+  FibonacciDpWithoutRecursion,
+  FibonacciRecursiveDP,
+  FibonacciIterative,
+  FibonacciRecursive
+} from '../Fibonacci'
+
+describe('Fibonanci', () => {
+  it('should return an array of numbers for FibonnaciIterative', () => {
+    expect(FibonacciIterative(5)).toEqual(
+      expect.arrayContaining([1, 1, 2, 3, 5])
+    )
+  })
+
+  it('should return an array of numbers for FibonnaciRecursive', () => {
+    expect(FibonacciRecursive(5)).toEqual(
+      expect.arrayContaining([1, 1, 2, 3, 5])
+    )
+  })
+
+  it('should return number for FibonnaciRecursiveDP', () => {
+    expect(FibonacciRecursiveDP(5)).toBe(5)
+  })
+
+  it('should return an array of numbers for FibonacciDpWithoutRecursion', () => {
+    expect(FibonacciDpWithoutRecursion(5)).toEqual(
+      expect.arrayContaining([1, 1, 2, 3, 5])
+    )
+  })
+})
diff --git a/Maths/test/FindHcf.test.js b/Maths/test/FindHcf.test.js
new file mode 100644
index 000000000..ccb5c3045
--- /dev/null
+++ b/Maths/test/FindHcf.test.js
@@ -0,0 +1,20 @@
+import { findHCF } from '../FindHcf'
+
+describe('findHCF', () => {
+  it('should throw a statement for values less than 1', () => {
+    expect(findHCF(0, 0)).toBe('Please enter values greater than zero.')
+  })
+
+  it('should throw a statement for one value less than 1', () => {
+    expect(findHCF(0, 1)).toBe('Please enter values greater than zero.')
+    expect(findHCF(1, 0)).toBe('Please enter values greater than zero.')
+  })
+
+  it('should return an error for values non-integer values', () => {
+    expect(findHCF(2.24, 4.35)).toBe('Please enter whole numbers.')
+  })
+
+  it('should return the HCF of two given integers', () => {
+    expect(findHCF(27, 36)).toBe(9)
+  })
+})
diff --git a/Maths/test/FindLcm.test.js b/Maths/test/FindLcm.test.js
new file mode 100644
index 000000000..1e5c0905c
--- /dev/null
+++ b/Maths/test/FindLcm.test.js
@@ -0,0 +1,20 @@
+import { findLcm } from '../FindLcm'
+
+describe('findLcm', () => {
+  it('should throw a statement for values less than 1', () => {
+    expect(findLcm(0, 0)).toBe('Please enter values greater than zero.')
+  })
+
+  it('should throw a statement for one value less than 1', () => {
+    expect(findLcm(1, 0)).toBe('Please enter values greater than zero.')
+    expect(findLcm(0, 1)).toBe('Please enter values greater than zero.')
+  })
+
+  it('should return an error for values non-integer values', () => {
+    expect(findLcm(4.564, 7.39)).toBe('Please enter whole numbers.')
+  })
+
+  it('should return the LCM of two given integers', () => {
+    expect(findLcm(27, 36)).toBe(108)
+  })
+})
diff --git a/Maths/test/GridGet.test.js b/Maths/test/GridGet.test.js
new file mode 100644
index 000000000..eef51fc6f
--- /dev/null
+++ b/Maths/test/GridGet.test.js
@@ -0,0 +1,16 @@
+import { gridGetX, gridGetY } from '../GridGet'
+
+describe('GridGet', () => {
+  it('should have a value of x for the 27th element if the square array has 400 elements', () => {
+    expect(gridGetX(Math.sqrt(400), 27)).toEqual(8)
+  })
+  it('should have a value of x for the 11th element if the square array has 7 columns and 3 rows', () => {
+    expect(gridGetX(7, 11)).toEqual(5)
+  })
+  it('should have a value of y for the 27th element if the square array has 400 elements', () => {
+    expect(gridGetY(Math.sqrt(400), 27)).toEqual(2)
+  })
+  it('should have a value of y for the 11th element if the square array has 7 columns and 3 rows ', () => {
+    expect(gridGetX(7, 11)).toEqual(5)
+  })
+})
diff --git a/Maths/test/MeanSquareError.test.js b/Maths/test/MeanSquareError.test.js
new file mode 100644
index 000000000..ecd53de89
--- /dev/null
+++ b/Maths/test/MeanSquareError.test.js
@@ -0,0 +1,21 @@
+import { meanSquaredError } from '../MeanSquareError'
+
+describe('meanSquareError', () => {
+  it('should throw an error on non-array arguments', () => {
+    expect(() => meanSquaredError(1, 4)).toThrow('Argument must be an Array')
+  })
+
+  it('should throw an error on non equal length ', () => {
+    const firstArr = [1, 2, 3, 4, 5]
+    const secondArr = [1, 2, 3]
+    expect(() => meanSquaredError(firstArr, secondArr)).toThrow(
+      'The two lists must be of equal length'
+    )
+  })
+
+  it('should return the mean square error of two equal length arrays', () => {
+    const firstArr = [1, 2, 3, 4, 5]
+    const secondArr = [1, 3, 5, 6, 7]
+    expect(meanSquaredError(firstArr, secondArr)).toBe(2.6)
+  })
+})
diff --git a/Maths/test/ModularBinaryExponentiationRecursive.test.js b/Maths/test/ModularBinaryExponentiationRecursive.test.js
new file mode 100644
index 000000000..9758d0ed1
--- /dev/null
+++ b/Maths/test/ModularBinaryExponentiationRecursive.test.js
@@ -0,0 +1,7 @@
+import { modularBinaryExponentiation } from '../ModularBinaryExponentiationRecursive'
+
+describe('modularBinaryExponentiation', () => {
+  it('should return the binary exponentiation', () => {
+    expect(modularBinaryExponentiation(2, 10, 17)).toBe(4)
+  })
+})
diff --git a/Maths/test/Palindrome.test.js b/Maths/test/Palindrome.test.js
new file mode 100644
index 000000000..53cb88395
--- /dev/null
+++ b/Maths/test/Palindrome.test.js
@@ -0,0 +1,16 @@
+import { PalindromeRecursive, PalindromeIterative } from '../Palindrome'
+
+describe('Palindrome', () => {
+  it('should return true for a palindrome for PalindromeRecursive', () => {
+    expect(PalindromeRecursive('mom')).toBeTruthy()
+  })
+  it('should return true  for a palindrome for PalindromeIterative', () => {
+    expect(PalindromeIterative('mom')).toBeTruthy()
+  })
+  it('should return false for a non-palindrome for PalindromeRecursive', () => {
+    expect(PalindromeRecursive('Algorithms')).toBeFalsy()
+  })
+  it('should return true  for a non-palindrome for PalindromeIterative', () => {
+    expect(PalindromeIterative('JavaScript')).toBeFalsy()
+  })
+})
diff --git a/Maths/test/PascalTriangle.test.js b/Maths/test/PascalTriangle.test.js
new file mode 100644
index 000000000..314d0f321
--- /dev/null
+++ b/Maths/test/PascalTriangle.test.js
@@ -0,0 +1,20 @@
+import { generate } from '../PascalTriangle'
+
+describe('Pascals Triangle', () => {
+  it('should have the the same length as the number', () => {
+    const pascalsTriangle = generate(5)
+    expect(pascalsTriangle.length).toEqual(5)
+  })
+  it('should have same length as its index in the array', () => {
+    const pascalsTriangle = generate(5)
+    pascalsTriangle.forEach((arr, index) => {
+      expect(arr.length).toEqual(index + 1)
+    })
+  })
+  it('should return an array of arrays', () => {
+    const pascalsTriangle = generate(3)
+    expect(pascalsTriangle).toEqual(
+      expect.arrayContaining([[1], [1, 1], [1, 2, 1]])
+    )
+  })
+})
diff --git a/Maths/test/PiApproximationMonteCarlo.test.js b/Maths/test/PiApproximationMonteCarlo.test.js
new file mode 100644
index 000000000..9727aa578
--- /dev/null
+++ b/Maths/test/PiApproximationMonteCarlo.test.js
@@ -0,0 +1,9 @@
+import { piEstimation } from '../PiApproximationMonteCarlo'
+
+describe('PiApproximationMonteCarlo', () => {
+  it('should be between the range of 2 to 4', () => {
+    const pi = piEstimation()
+    const piRange = pi >= 2 && pi <= 4
+    expect(piRange).toBeTruthy()
+  })
+})
diff --git a/Maths/test/Polynomial.test.js b/Maths/test/Polynomial.test.js
new file mode 100644
index 000000000..af5618ab3
--- /dev/null
+++ b/Maths/test/Polynomial.test.js
@@ -0,0 +1,37 @@
+import { Polynomial } from '../Polynomial'
+
+describe('Polynomial', () => {
+  it('should not return a expression for zero', () => {
+    const polynomial = new Polynomial([0])
+    expect(polynomial.display()).toBe('')
+  })
+  it('should not return an expression for zero values', () => {
+    const polynomial = new Polynomial([0, 0, 0, 0, 0])
+    expect(polynomial.display()).toBe('')
+  })
+  it('should return an expression for single a non zero value', () => {
+    const polynomial = new Polynomial([9])
+    expect(polynomial.display()).toBe('(9)')
+  })
+  it('should return an expression for two values', () => {
+    const polynomial = new Polynomial([3, 2])
+    expect(polynomial.display()).toBe('(2x) + (3)')
+  })
+  it('should return an expression for values including zero', () => {
+    const polynomial = new Polynomial([0, 2])
+    expect(polynomial.display()).toBe('(2x)')
+  })
+  it('should return an expression and evaluate it', () => {
+    const polynomial = new Polynomial([1, 2, 3, 4])
+    expect(polynomial.display()).toBe('(4x^3) + (3x^2) + (2x) + (1)')
+    expect(polynomial.evaluate(2)).toEqual(49)
+  })
+  it('should evaluate 0 for zero values', () => {
+    const polynomial = new Polynomial([0, 0, 0, 0])
+    expect(polynomial.evaluate(5)).toEqual(0)
+  })
+  it('should evaluate for negative values', () => {
+    const polynomial = new Polynomial([-1, -3, -4, -7])
+    expect(polynomial.evaluate(-5)).toBe(789)
+  })
+})
diff --git a/Maths/test/PrimeCheck.test.js b/Maths/test/PrimeCheck.test.js
new file mode 100644
index 000000000..da1cd1b52
--- /dev/null
+++ b/Maths/test/PrimeCheck.test.js
@@ -0,0 +1,14 @@
+import { PrimeCheck } from '../PrimeCheck'
+
+describe('PrimeCheck', () => {
+  it('should return true for Prime Numbers', () => {
+    expect(PrimeCheck(1000003)).toBeTruthy()
+  })
+  it('should return false for Non Prime Numbers', () => {
+    expect(PrimeCheck(1000001)).toBeFalsy()
+  })
+  it('should return false for 1 and 0', () => {
+    expect(PrimeCheck(1)).toBeFalsy()
+    expect(PrimeCheck(0)).toBeFalsy()
+  })
+})
diff --git a/Maths/test/ReversePolishNotation.test.js b/Maths/test/ReversePolishNotation.test.js
new file mode 100644
index 000000000..8b880ee47
--- /dev/null
+++ b/Maths/test/ReversePolishNotation.test.js
@@ -0,0 +1,11 @@
+import { calcRPN } from '../ReversePolishNotation'
+
+describe('ReversePolishNotation', () => {
+  it('should evaluate correctly for two values', () => {
+    expect(calcRPN('2 3 +')).toEqual(5)
+  })
+  it("should evaluate' for multiple values", () => {
+    expect(calcRPN('2 2 2 * +')).toEqual(6)
+    expect(calcRPN('6 9 7 + 2 / + 3 *')).toEqual(42)
+  })
+})
diff --git a/Maths/test/SieveOfEratosthenes.test.js b/Maths/test/SieveOfEratosthenes.test.js
new file mode 100644
index 000000000..056693d39
--- /dev/null
+++ b/Maths/test/SieveOfEratosthenes.test.js
@@ -0,0 +1,14 @@
+import { sieveOfEratosthenes } from '../SieveOfEratosthenes'
+import { PrimeCheck } from '../PrimeCheck'
+
+describe('should return an array of prime booleans', () => {
+  it('should have each element in the array as a prime boolean', () => {
+    const n = 30
+    const primes = sieveOfEratosthenes(n)
+    primes.forEach((primeBool, index) => {
+      if (primeBool) {
+        expect(PrimeCheck(index)).toBeTruthy()
+      }
+    })
+  })
+})
diff --git a/String/PatternMatching.js b/String/PatternMatching.js
index 3148f85cd..b90260ce7 100644
--- a/String/PatternMatching.js
+++ b/String/PatternMatching.js
@@ -24,7 +24,6 @@ const checkIfPatternExists = (text, pattern) => {
       // For each iteration of j check if the value of
       // j + 1 is equal to the length of the pattern
       if (j + 1 === patternLength) {
-        console.log(`Given pattern is found at index ${i}`)
         return `Given pattern is found at index ${i}`
       }
     }
diff --git a/String/CheckAnagram.test.js b/String/test/CheckAnagram.test.js
similarity index 92%
rename from String/CheckAnagram.test.js
rename to String/test/CheckAnagram.test.js
index e5016f752..691d5ba89 100644
--- a/String/CheckAnagram.test.js
+++ b/String/test/CheckAnagram.test.js
@@ -1,4 +1,4 @@
-import { checkAnagram } from './CheckAnagram'
+import { checkAnagram } from '../CheckAnagram'
 
 describe('checkAnagram', () => {
   it.each`
@@ -18,7 +18,7 @@ describe('checkAnagram', () => {
   )
   it('expects to return "Not anagram" if the arguments have different lengths', () => {
     const SUT = checkAnagram('abs', 'abds')
-    expect(SUT).toBe('Not Anagram')
+    expect(SUT).toBe('Not anagrams')
   })
   it('expects to return "Not anagram" if the arguments are not anagrams', () => {
     const SUT = checkAnagram('abcs', 'abds')
diff --git a/String/CheckPalindrome.test.js b/String/test/CheckPalindrome.test.js
similarity index 90%
rename from String/CheckPalindrome.test.js
rename to String/test/CheckPalindrome.test.js
index 3bd401ba1..cfe88f7e5 100644
--- a/String/CheckPalindrome.test.js
+++ b/String/test/CheckPalindrome.test.js
@@ -1,4 +1,4 @@
-import { checkPalindrome } from './CheckPalindrome'
+import { checkPalindrome } from '../CheckPalindrome'
 
 describe('checkPalindrome', () => {
   it('expects to return "Palindrome" if the given string is a palindrome', () => {
diff --git a/String/PatternMatching.test.js b/String/test/PatternMatching.test.js
similarity index 84%
rename from String/PatternMatching.test.js
rename to String/test/PatternMatching.test.js
index 23e892dd7..d0eab80b6 100644
--- a/String/PatternMatching.test.js
+++ b/String/test/PatternMatching.test.js
@@ -1,4 +1,4 @@
-import { checkIfPatternExists } from './PatternMatching'
+import { checkIfPatternExists } from '../PatternMatching'
 describe('checkIfPatternExists', () => {
   it('expects to find a pattern with correct input', () => {
     const text = 'AABAACAADAABAAAABAA'
@@ -21,6 +21,8 @@ describe('checkIfPatternExists', () => {
   it('expects to throw an error message when given inpuut is not a string', () => {
     const text = 123444456
     const pattern = 123
-    expect(() => checkIfPatternExists(text, pattern)).toThrow('Given input is not a string')
+    expect(() => checkIfPatternExists(text, pattern)).toThrow(
+      'Given input is not a string'
+    )
   })
 })
diff --git a/String/ReverseString.test.js b/String/test/ReverseString.test.js
similarity index 98%
rename from String/ReverseString.test.js
rename to String/test/ReverseString.test.js
index 1658c8bde..6ec1bb4df 100644
--- a/String/ReverseString.test.js
+++ b/String/test/ReverseString.test.js
@@ -1,7 +1,7 @@
 import {
   ReverseStringIterative,
   ReverseStringIterativeInplace
-} from './ReverseString'
+} from '../ReverseString'
 
 describe('ReverseStringIterative', () => {
   it('expects to reverse a simple string', () => {
diff --git a/String/ReverseWords.test.js b/String/test/ReverseWords.test.js
similarity index 90%
rename from String/ReverseWords.test.js
rename to String/test/ReverseWords.test.js
index 7c4aa16dd..32bd9d462 100644
--- a/String/ReverseWords.test.js
+++ b/String/test/ReverseWords.test.js
@@ -1,4 +1,4 @@
-import { reverseWords } from './ReverseWords'
+import { reverseWords } from '../ReverseWords'
 
 describe('reverseWords', () => {
   it('expects to reverse words to return a joined word', () => {