Glasgow | Jan-26 | Elisabeth Matulian | Sprint 1 | Exercises

Sprint-1/fix/median.js

@@ -6,9 +6,21 @@
 // or 'list' has mixed values (the function is expected to sort only numbers).
 
 function calculateMedian(list) {
-  const middleIndex = Math.floor(list.length / 2);
-  const median = list.splice(middleIndex, 1)[0];
-  return median;
+  if (Array.isArray(list)) {
+    let newList = list.filter(item => typeof item === "number");
+    newList = newList.sort(function (a, b) {
+      return a - b;
+    });
+    if (newList.length > 0){
+      const middleIndex = Math.floor(newList.length / 2);
+      const median = newList[middleIndex]
+      if (newList.length % 2 !== 0) {
+        return median;
+    }
+      else return (newList[middleIndex - 1] + median) / 2}
+    else return null;}
+  else return null;
 }
 
 module.exports = calculateMedian;
+

Sprint-1/implement/dedupe.js

@@ -1 +1,7 @@
-function dedupe() {}
+function dedupe(arr) {
+    let newArr = new Set(arr);
+    return Array.from(newArr)
+}
+
+
+module.exports = dedupe;

Sprint-1/implement/dedupe.test.js

@@ -16,12 +16,21 @@ E.g. dedupe([1, 2, 1]) target output: [1, 2]
 // Given an empty array
 // When passed to the dedupe function
 // Then it should return an empty array
-test.todo("given an empty array, it returns an empty array");
+//test.todo("given an empty array, it returns an empty array");
+test("given an empty array, it should return an empty array", () => {
+    expect(dedupe([])).toEqual([]);
+});
 
 // Given an array with no duplicates
 // When passed to the dedupe function
 // Then it should return a copy of the original array
+test("given an array with no duplicates, it should return a copy of the original array", () => {
+    expect(dedupe(['4', 'text'])).toEqual(['4', 'text']);
+});
 
 // Given an array with strings or numbers
 // When passed to the dedupe function
 // Then it should remove the duplicate values, preserving the first occurence of each element
+test("given an array with strings or numbers, it should remove the duplicate values, preserving the first occurence of each element", () => {
+    expect(dedupe([4, '4', 'test', 4, 5, 5, 10, 'test'])).toEqual([4, '4', 'test', 5, 10]);
+});

Sprint-1/implement/max.js

@@ -1,4 +1,9 @@
 function findMax(elements) {
+    let newList = elements.filter(item => typeof item === "number");
+    if (newList.length > 0) {
+        return Math.max(...newList)
+    }
+    else return -Infinity
 }
 
 module.exports = findMax;

Sprint-1/implement/max.test.js

@@ -16,28 +16,49 @@ const findMax = require("./max.js");
 // When passed to the max function
 // Then it should return -Infinity
 // Delete this test.todo and replace it with a test.
-test.todo("given an empty array, returns -Infinity");
+//test.todo("given an empty array, returns -Infinity");
+test("given an empty array, returns -Infinity", () => {
+    expect(findMax([])).toBe(-Infinity);
+});
 
 // Given an array with one number
 // When passed to the max function
 // Then it should return that number
+test("given an array with one number, it should return that number", () => {
+    expect(findMax([2])).toBe(2);
+});
 
 // Given an array with both positive and negative numbers
 // When passed to the max function
 // Then it should return the largest number overall
+test("given an array with both positive and negative numbers, it returns the largest number", () => {
+    expect(findMax([3, -3])).toBe(3);
+});
 
 // Given an array with just negative numbers
 // When passed to the max function
 // Then it should return the closest one to zero
+test("given an array with just negative numbers, it returns the closest one to zero", () => {
+    expect(findMax([-1, -5, -2])).toBe(-1);
+});
 
 // Given an array with decimal numbers
 // When passed to the max function
 // Then it should return the largest decimal number
+test("given an array with decimal numbers, it returns the largest decimal number", () => {
+    expect(findMax([1.5, 20.3, 4.1])).toBe(20.3);
+});
 
 // Given an array with non-number values
 // When passed to the max function
 // Then it should return the max and ignore non-numeric values
+test("given an array with non-number values, it returns the max and ignore non-numeric values", () => {
+    expect(findMax([null, 15, 'text', false, 4, Infinity])).toBe(Infinity);
+});
 
 // Given an array with only non-number values
 // When passed to the max function
 // Then it should return the least surprising value given how it behaves for all other inputs
+test("given an array with only non-number values, it returns the least surprising value given how it behaves for all other inputs", () => {
+    expect(findMax(['text', false, null, undefined, ])).toBe(-Infinity);
+});

Sprint-1/implement/sum.js

@@ -1,4 +1,11 @@
 function sum(elements) {
+    let counter = 0;
+    for (const el of elements) {
+        if (typeof el === 'number') {
+            counter += el;
+        }
+    }
+    return counter;
 }
 
 module.exports = sum;

Sprint-1/implement/sum.test.js

@@ -13,24 +13,42 @@ const sum = require("./sum.js");
 // Given an empty array
 // When passed to the sum function
 // Then it should return 0
-test.todo("given an empty array, returns 0")
+// test.todo("given an empty array, returns 0")
 
+test("given an empty array, returns 0", () => {
+    expect(sum([])).toBe(0);
+});
 // Given an array with just one number
 // When passed to the sum function
 // Then it should return that number
+test("given an array with just one number, return that number", () => {
+    expect(sum([5])).toBe(5);
+});
 
 // Given an array containing negative numbers
 // When passed to the sum function
 // Then it should still return the correct total sum
+test("given an array containing negative numbers, return the correct total sum", () => {
+    expect(sum([5, -3, 9, 2, -1])).toBe(12);
+});
 
 // Given an array with decimal/float numbers
 // When passed to the sum function
 // Then it should return the correct total sum
+test("given an array containing decimal/float numbers the correct total sum", () => {
+    expect(sum([5.1, 3.2, 6.5])).toBe(14.8);
+});
 
 // Given an array containing non-number values
 // When passed to the sum function
 // Then it should ignore the non-numerical values and return the sum of the numerical elements
+test("given an array containing non-number values, return the sum of the numerical elements", () => {
+    expect(sum([5, null, '6', 3])).toBe(8);
+});
 
 // Given an array with only non-number values
 // When passed to the sum function
 // Then it should return the least surprising value given how it behaves for all other inputs
+test("given an array with only non-number values, return return the least surprising value given how it behaves for all other inputs", () => {
+    expect(sum(['5', undefined, true])).toBe(0);
+});

Sprint-1/refactor/includes.js

@@ -1,8 +1,9 @@
 // Refactor the implementation of includes to use a for...of loop
 
 function includes(list, target) {
-  for (let index = 0; index < list.length; index++) {
-    const element = list[index];
+  // for (let index = 0; index < list.length; index++) {
+  //   const element = list[index];
+  for (const element of list) {
     if (element === target) {
       return true;
     }