London | 26-ITP-Jan | Carlos Abreu |Sprint 1 | Data Module Groups

Sprint-1/fix/median.js

@@ -6,9 +6,32 @@
 // 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;
+  // Check if input is an array
+  if (!Array.isArray(list)) {
+    return null;
+  }
+
+  // Filter out non-numbers (keep only numbers)
+  const numbers = list.filter(item => typeof item === 'number' && !isNaN(item));
+
+  // If no numbers in the array, return null
+  if (numbers.length === 0) {
+    return null;
+  }
+
+  // Sort the numbers in ascending order
+  const sorted = [...numbers].sort((a, b) => a - b);
+
+  const middleIndex = Math.floor(sorted.length / 2);
+
+  // If length is odd, return the middle element
+  if (sorted.length % 2 !== 0) {
+    return sorted[middleIndex];
+  }
+  // If length is even, return the average of the two middle elements
+  else {
+    return (sorted[middleIndex - 1] + sorted[middleIndex]) / 2;
+  }
 }
 
 module.exports = calculateMedian;

Sprint-1/implement/dedupe.js

@@ -1 +1,7 @@
-function dedupe() {}
+function dedupe(elements) {
+    // Using a Set to remove duplicates while preserving insertion order
+    // Then spread the Set back into an array
+    return [...new Set(elements)];
+}
+
+module.exports = dedupe;

Sprint-1/implement/dedupe.test.js

@@ -16,13 +16,51 @@ E.g. dedupe([1, 2, 1]) returns [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", () => {
+    const arr1 = [1, 2, 3, 4, 5];
+    expect(dedupe(arr1)).toEqual([1, 2, 3, 4, 5]);
+    expect(dedupe(arr1)).not.toBe(arr1); // Should be a copy, not the same reference
+
+    const arr2 = ['a', 'b', 'c', 'd'];
+    expect(dedupe(arr2)).toEqual(['a', 'b', 'c', 'd']);
+
+    const arr3 = [10, 20, 30];
+    expect(dedupe(arr3)).toEqual([10, 20, 30]);
+});
 
 // Given an array of strings or numbers
 // When passed to the dedupe function
-// Then it should return a new array with duplicates removed while preserving the 
-// first occurrence of each element from the original array.
+// Then it should remove the duplicate values, preserving the first occurrence of each element
+test("given an array with strings or numbers, it removes duplicate values, preserving the first occurrence of each element", () => {
+    // String duplicates
+    expect(dedupe(['a', 'a', 'a', 'b', 'b', 'c'])).toEqual(['a', 'b', 'c']);
+
+    // Number duplicates
+    expect(dedupe([5, 1, 1, 2, 3, 2, 5, 8])).toEqual([5, 1, 2, 3, 8]);
+
+    // Mixed duplicates
+    expect(dedupe([1, 2, 1])).toEqual([1, 2]);
+
+    // Multiple duplicate occurrences
+    expect(dedupe([1, 2, 2, 3, 3, 3, 4, 4, 4, 4])).toEqual([1, 2, 3, 4]);
+
+    // Different data types (they're distinct, so no duplicates)
+    expect(dedupe([1, '1', 1, '1'])).toEqual([1, '1']);
+
+    // Mixed types with duplicates within same type
+    expect(dedupe(['x', 'y', 'x', 'z', 'y', 'x'])).toEqual(['x', 'y', 'z']);
+
+    // Numbers in different order
+    expect(dedupe([3, 1, 4, 1, 5, 9, 2, 6, 5, 3, 5])).toEqual([3, 1, 4, 5, 9, 2, 6]);
+
+    // Single element array
+    expect(dedupe([42])).toEqual([42]);
+    expect(dedupe(['hello'])).toEqual(['hello']);
+});

Sprint-1/implement/max.js

@@ -1,4 +1,15 @@
+
 function findMax(elements) {
+    // Filter out non-numeric values
+    const numbers = elements.filter(element => typeof element === 'number');
+
+    // If no numbers in array, return -Infinity
+    if (numbers.length === 0) {
+        return -Infinity;
+    }
+
+    // Find and return the maximum value
+    return Math.max(...numbers);
 }
 
 module.exports = findMax;

Sprint-1/implement/max.test.js

@@ -1,43 +1,62 @@
-/* Find the maximum element of an array of numbers
-
-In this kata, you will need to implement a function that find the largest numerical element of an array.
-
-E.g. max([30, 50, 10, 40]), target output: 50
-E.g. max(['hey', 10, 'hi', 60, 10]), target output: 60 (sum ignores any non-numerical elements)
-
-You should implement this function in max.js, and add tests for it in this file.
-
-We have set things up already so that this file can see your function from the other file.
-*/
-
 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, 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, returns that number", () => {
+    expect(findMax([42])).toBe(42);
+    expect(findMax([-10])).toBe(-10);
+    expect(findMax([0])).toBe(0);
+});
 
 // 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, returns the largest number overall", () => {
+    expect(findMax([30, 50, 10, 40])).toBe(50);
+    expect(findMax([-5, 10, -20, 30])).toBe(30);
+    expect(findMax([-100, -200, 0, 150])).toBe(150);
+});
 
 // 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, returns the closest one to zero", () => {
+    expect(findMax([-5, -10, -3, -8])).toBe(-3);
+    expect(findMax([-1, -100, -50])).toBe(-1);
+    expect(findMax([-0.5, -0.8, -0.1])).toBe(-0.1);
+});
 
 // 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, returns the largest decimal number", () => {
+    expect(findMax([1.5, 2.7, 1.2, 3.8])).toBe(3.8);
+    expect(findMax([-1.5, -2.7, -1.2, -0.5])).toBe(-0.5);
+    expect(findMax([0.1, 0.01, 0.001])).toBe(0.1);
+});
 
 // 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, returns the max and ignores non-numeric values", () => {
+    expect(findMax(['hey', 10, 'hi', 60, 10])).toBe(60);
+    expect(findMax([20, 'abc', 30, 'def', 40])).toBe(40);
+    expect(findMax(['x', 'y', 'z', 100, 50])).toBe(100);
+});
 
 // 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, returns -Infinity", () => {
+    expect(findMax(['hey', 'hi', 'hello'])).toBe(-Infinity);
+    expect(findMax([true, false, null])).toBe(-Infinity);
+    expect(findMax([{}, [], 'string'])).toBe(-Infinity);
+});

Sprint-1/implement/sum.js

@@ -1,4 +1,9 @@
 function sum(elements) {
+    // Filter out non-numeric values
+    const numbers = elements.filter(element => typeof element === 'number');
+
+    // Sum all the numbers using reduce
+    return numbers.reduce((total, current) => total + current, 0);
 }
 
 module.exports = sum;

Sprint-1/implement/sum.test.js

@@ -1,36 +1,59 @@
-/* Sum the numbers in an array
-
-In this kata, you will need to implement a function that sums the numerical elements of an array
-
-E.g. sum([10, 20, 30]), target output: 60
-E.g. sum(['hey', 10, 'hi', 60, 10]), target output: 80 (ignore any non-numerical elements)
-*/
-
 const sum = require("./sum.js");
 
-// Acceptance Criteria:
-
 // 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, 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, returns that number", () => {
+    expect(sum([42])).toBe(42);
+    expect(sum([-10])).toBe(-10);
+    expect(sum([0])).toBe(0);
+    expect(sum([3.14])).toBe(3.14);
+});
 
 // 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, returns the correct total sum", () => {
+    expect(sum([10, -5, 20, -3])).toBe(22);
+    expect(sum([-10, -20, -30])).toBe(-60);
+    expect(sum([5, -5, 10, -10])).toBe(0);
+    expect(sum([-1, -2, -3, -4])).toBe(-10);
+});
 
 // 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 with decimal/float numbers, returns the correct total sum", () => {
+    expect(sum([1.5, 2.5, 3.0])).toBe(7);
+    expect(sum([0.1, 0.2, 0.3])).toBeCloseTo(0.6);
+    expect(sum([1.99, 2.99, 3.99])).toBeCloseTo(8.97);
+    expect(sum([-1.5, 2.5, -1.0])).toBe(0);
+});
 
 // 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, ignores non-numerical values and returns sum of numerical elements", () => {
+    expect(sum(['hey', 10, 'hi', 60, 10])).toBe(80);
+    expect(sum([20, 'abc', 30, 'def', 40])).toBe(90);
+    expect(sum(['x', 'y', 'z', 100, 50])).toBe(150);
+    expect(sum([true, 5, false, 10, null, 15])).toBe(30);
+    expect(sum([{}, [], 25, 'string', 35])).toBe(60);
+});
 
 // 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, returns 0", () => {
+    expect(sum(['hey', 'hi', 'hello'])).toBe(0);
+    expect(sum([true, false, null])).toBe(0);
+    expect(sum([{}, [], 'string', undefined])).toBe(0);
+    expect(sum(['a', 'b', 'c'])).toBe(0);
+});