Functions Lab

Introduction

Note: This can be a pair programming activity or done independently.

This lab provides an opportunity to pracitce implementing some real-world functions.

Exercise

Requirements

Please write code that implements various functions, following the requirements in the list below:

1. Fork this repo
2. Clone this repo into your ~/code/labs
3. Define a function maxOfTwoNumbers that takes two numbers as arguments and returns the largest of them. Use the if-then-else construct available in Javascript. Do some googling to figure this out if you forget how conditionals work.
4. Define a function maxOfThree that takes three numbers as arguments and returns the largest of them.
5. Write a function isCharacterAVowel that takes a character (i.e. a string of length 1) and returns true if it is a vowel, false otherwise.
6. Define a function sumArray and a function multiplyArray that sums and multiplies (respectively) all the numbers in an array of numbers. For example, sumArray([1,2,3,4]) should return 10, and multiplyArray([1,2,3,4]) should return 24.
7. Write a function that return the number of arguments passed to the function when called.
8. Define a function reverseString that computes the reversal of a string. For example, reverseString("jag testar") should return the string "ratset gaj".
9. Write a function findLongestWord that takes an array of words and returns the length of the longest one.
10. Write a function filterLongWords that takes an array of words and a number i and returns the array of words that are longer than i characters long.

Bonus

1. Attach the function reverseString (from question 6) to the object String so that it is possible to call: "General Assembly".reverseString().
2. Write a function that takes a string as argument and returns an object where:

• the keys are the characters that occur in the string
• the values are the number of occurences for each letter, regardless of the case

For example, calling the function with the string "General Assembly" will return:

{
  a: 2,
  b: 1,
  e: 3,
  g: 1,
  l: 2,
  m: 1,
  n: 1,
  r: 1,
  s: 2,
  y: 1
}

Submission

1. Upon completion, run the following commands

git add .
git commit -m "done"
git push origin master

1. Navigate to your repo and create a Pull Request
2. Put the link to Pull Request to the Student Excel File

Starter Code

Open the file functions.js. All the function names are already inside the file, you just need to implement them by adding code inside each one.

Use the Chrome dev tools console to practice executing your code.

Deliverable

You'll review the answers with the instructor in class.

Additional Resources

• MDN Functions