Glasgow | 26-ITP-Jan| Martin McLean |Sprint 1| coursework

Sprint-1/fix/median.js

@@ -6,9 +6,27 @@
 // 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;
+  list = list || [];
+  let newOrder = Array.from(list);
+  let i = 0;
+  while (i < newOrder.length) {
+    if (typeof newOrder[i] !== "number") newOrder.splice(i, 1);
+    else i++;
+  }
+  if (newOrder.length === 0) {
+    return null;
+  }
+  newOrder = newOrder.sort((a, b) => a - b);
+  const middleIndex = Math.floor(newOrder.length / 2);
+  if (newOrder.length % 2 !== 0) {
+    return newOrder[middleIndex];
+  } else {
+    const middleTwo = (newOrder[middleIndex] + newOrder[middleIndex - 1]) / 2;
+    return middleTwo;
+  }
 }
-
 module.exports = calculateMedian;
+console.log(calculateMedian([110, 20, 0]));
+console.log(calculateMedian([3, "apple", 1, 2, undefined, 4]));
+console.log(calculateMedian([]));
+console.log(calculateMedian(["frog", "dog", "log", "cog"]));

Sprint-1/implement/dedupe.js

@@ -1 +1,6 @@
-function dedupe() {}
+function dedupe(elements) {
+  const noDupe = [...new Set(elements)];
+  return noDupe;
+}
+console.log(dedupe([3, 3, 3, 4, 5, 4, "cat", "dog", "cat", 6, 1, 2, 3, 1]));
+module.exports = dedupe;

Sprint-1/implement/dedupe.test.js

@@ -16,12 +16,23 @@ 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("given an empty array, it returns 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 returns a copy of the original array", () => {
+  expect(dedupe([1, 2, 3])).toEqual([1, 2, 3]);
+  expect(dedupe(["a", "b", "c"])).toEqual(["a", "b", "c"]);
+});
 
 // 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 removes duplicates preserving first occurrence", () => {
+  expect(dedupe(["a", "a", "b", "c", "c"])).toEqual(["a", "b", "c"]);
+  expect(dedupe([1, 2, 2, 3, 4, 4])).toEqual([1, 2, 3, 4]);
+  expect(dedupe([4, 6, "hi", 4, 6, "hi"])).toEqual([4, 6, "hi"]);
+});

Sprint-1/implement/max.js

@@ -1,4 +1,10 @@
 function findMax(elements) {
+  const numbers = elements.filter((element) => typeof element === "number");
+  if (numbers.length === 0) {
+    return -Infinity;
+  }
+  numbers.sort((a, b) => a - b);
+  return numbers[numbers.length - 1];
 }
 
 module.exports = findMax;

Sprint-1/implement/max.test.js

@@ -15,29 +15,57 @@ const findMax = require("./max.js");
 // Given an empty array
 // 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("Given an empty array Then it should return -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, returns that number", () => {
+  expect(findMax([2])).toEqual(2);
+  expect(findMax([7])).toEqual(7);
+  expect(findMax([-7])).toEqual(-7);
+  expect(findMax([70000000])).toEqual(70000000);
+});
 
 // 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 Then it should return the largest number overall", () => {
+  expect(findMax([2, -9])).toEqual(2);
+  expect(findMax([2, -4, -2, 9])).toEqual(9);
+});
 
 // 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 Then it should return the closest one to zero", () => {
+  expect(findMax([-2, -4, -1, -99])).toEqual(-1);
+  expect(findMax([2])).toEqual(2);
+});
 
 // 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 just negative numbers Then it should return the closest one to zero", () => {
+  expect(findMax([3.7, 3.8, 3.9])).toEqual(3.9);
+  expect(findMax([2.8, 2.6, 2.5, 2.1])).toEqual(2.8);
+});
 
 // 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 just negative numbers Then it should return the closest one to zero", () => {
+  expect(findMax([-2, -4, -1, "p"])).toEqual(-1);
+  expect(findMax([2, 5, "i", 3, "r"])).toEqual(5);
+});
 
 // 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
+// Then it should return the least surprising value given how it behaves for all other input
+test("Given an array with only non-number values Then it should return the least surprising value given how it behaves for all other input", () => {
+  expect(findMax(["cat"])).toEqual(-Infinity);
+  expect(findMax(["cat", "dog"])).toEqual(-Infinity);
+  expect(findMax(["cat", "dog", "catdog"])).toEqual(-Infinity);
+});

Sprint-1/implement/sum.js

@@ -1,4 +1,11 @@
 function sum(elements) {
-}
+  let total = 0;
+  const numbers = elements.filter((element) => typeof element === "number");
 
+  numbers.forEach((numb) => {
+    total = total + numb;
+  });
+  return total;
+}
+console.log(sum([5]));
 module.exports = sum;

Sprint-1/implement/sum.test.js

@@ -13,24 +13,45 @@ 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("Given an empty array Then it should return 0", () => {
+  expect(sum([])).toEqual(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 one element it should return that number", () => {
+  expect(sum([4])).toEqual(4);
+  expect(sum([10000])).toEqual(10000);
+});
 
 // Given an array containing negative numbers
 // When passed to the sum function
 // Then it should still return the correct total sum
+test("Given negitave numbers still sums correctly", () => {
+  expect(sum([2, 3, -3])).toEqual(2);
+  expect(sum([5, -3, -3])).toEqual(-1);
+});
 
 // Given an array with decimal/float numbers
 // When passed to the sum function
 // Then it should return the correct total sum
+test("Given a float number it still sums correctly", () => {
+  expect(sum([4.2, 4.3])).toEqual(8.5);
+  expect(sum([2.223, 5.345, 3.141])).toEqual(10.709);
+  expect(sum([3.887, 2.1945, -3.5])).toEqual(2.5815);
+});
 
 // 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 non-numerical values should ignore and sum the numbers", () => {
+  expect(sum([4, "four", "fore", "iv", 4])).toEqual(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 only non-numerical values should return 0", () => {
+  expect(sum(["tommorow", "and", "tommorow", "and", "tommorow"]));
+});

Sprint-1/refactor/includes.js

@@ -1,8 +1,7 @@
 // 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 (const element of list) {
     if (element === target) {
       return true;
     }