JavaScript Basics Assessment

Core competencies assessed

• Reading and following directions

• Producing solutions that match the problem specification

• Using Git and working with GitHub

  • Cloning a git repository from GitHub
  • Creating your own branch
  • Committing and pushing work to a new branch on GitHub

• Programing fundamentals in JavaScript

  • Working with values, variables, and data types
  • Using assignment and comparision operators
  • Working with JS internal functions to make decisions and perform actions.
  • Using conditional logic to make decisions inside functions
  • Writing functions that take in inputs, process, and return outputs.

Instructions

0. Carefully read all the instructions and problems before beginning your work.

1. Clone this repository to your local projects directory. If you're using IntelliJ, go to File->New->Project From Version Control->GitHub and then paste the clone address of this repo. The clone address of the repo is found by clicking the green "Clone or download" button on the repo's page.

2. Create a branch named firstName-lastLastname where firstName is your first name and lastName is your last name. In IntelliJ, go to VCS, then Git, then Branches, and click "+ New Branch" and name it accordingly.

3. Write your solutions to the problems presented below inside solutions.js.

4. Read the Testing instructions below.

5. Add, commit often (preferably every time you finish a problem), and only push your firstName-lastName branch to GitHub when an instructor tells you to.

Problems

1. Define a function named lowerCase that takes in an input and returns that input as a string in all lower case letters. Returns false if the input passed is not a string.

lowerCase('CODEUP')                             // codeup
lowerCase('George WashingTon')                  // george washington
lowerCase(0)                                    // false
lowerCase(true)                                 // false
lowerCase('BoBby')                              // bobby
lowerCase(null)                                 // false
lowerCase([1,2,3])                              // false
lowerCase({fName: 'Bruce', lName: 'Wayne'})     // false

2. Define a function named isAllLowerCase that takes in a string and returns true if all characters in the string are lowercase otherwise it should return false.

isAllLowerCase('codeup')                            // true
isAllLowerCase('hello there')                       // true
isAllLowerCase('BoBby')                             // false
isAllLowerCase('George WashingTon')                 // false
isAllLowerCase(0)                                   // false
isAllLowerCase(true)                                // false
isAllLowerCase(null)                                // false
isAllLowerCase([1,2,3])                             // false
isAllLowerCase({fName: 'Bruce', lName: 'Wayne'})    // false

3. Define a function named isAllUpperCase that takes in a string and returns true if all characters in the string are uppercase otherwise it should return false.

isAllUpperCase('CODEUP')                            // true
isAllUpperCase('HELLO THERE')                       // true
isAllUpperCase('BoBby')                             // false
isAllUpperCase('codeup')                            // false
isAllUpperCase('George WashingTon')                 // false
isAllUpperCase(0)                                   // false
isAllUpperCase(true)                                // false
isAllUpperCase(null)                                // false
isAllUpperCase([1,2,3])                             // false
isAllUpperCase({fName: 'Bruce', lName: 'Wayne'})    // false

4. Define a function named isNotPalindrome that takes in a string and returns true if that string is not palindrome, if the string is palindrome should return false.

isNotPalindrome('Kayak')                             // false
isNotPalindrome('George WashingTon')                 // true
isNotPalindrome(0)                                   // true
isNotPalindrome(true)                                // true
isNotPalindrome('civic')                             // false
isNotPalindrome(null)                                // true
isNotPalindrome()                                    // true
isNotPalindrome([1,2,3])                             // true
isNotPalindrome({fName: 'Bruce', lName: 'Wayne'})    // true

5. Define a function named multiplyBy2 that takes in an input and multiplies it by 2 if the input is numeric. If the input is Not A Number, then return false.

multiplyBy2(2)                     // 4
multiplyBy2("4")                   // 8
multiplyBy2("-5.5")                // -11.0
multiplyBy2(5.5)                   // 11
multiplyBy2(null)                  // false
multiplyBy2(true)                  // false
multiplyBy2(false)                 // false

6. Define a function named convertHourToSec that takes in one input Hours. Return the conversation of the number of hours into total seconds. If the input is not numeric or a numeric string, convertHourToSec, should return false.

convertHourToSec(0)                 // 0
convertHourToSec(1)                 // 3600
convertHourToSec(1.5)               // 5400
convertHourToSec(true)              // false
convertHourToSec(-1)                // false
convertHourToSec(null)              // false
convertHourToSec("2")               // 7200

7. Write a function named getLowestNumber that takes in 3 arguments. If all 3 inputs are numbers or numeric strings, then return the lowest number. If any of the 3 inputs is missing or non-numeric, then return false.

getLowestNumber(1, 3, 2)            // 1
getLowestNumber("0", 1, 2)          // 0
getLowestNumber(9, 3, -20)          // -20
getLowestNumber(2, 2, 2)            // 2
getLowestNumber(2, 5, 5)            // 2
getLowestNumber(1, 2, 'x')          // false
getLowestNumber("a", "b")           // false
getLowestNumber()                   // false

8. Write a function named addStringLengths that takes in two inputs. If both inputs provided are strings, addStringLengths returns the sum after adding the length (number of characters) of both strings. If either or both inputs are not strings, return false.

addStringLengths(1, 2)                       // false
addStringLengths("code", "up")               // 6
addStringLengths("1 2 3", "4 5 6")           // 10
addStringLengths("ranking", 1)               // false
addStringLengths(null, null)                 // false
addStringLengths(true, false)                // false
addStringLengths(["code", "up"], "rocks!")   // false
addStringLengths("", ""));                   // 0

9. Write a function named subtract that takes in two inputs. If both inputs provided are numeric or numeric strings, subtract will return the difference when the second input is subtracted from the first input. If one or both inputs is not numeric or numeric strings, subtract should return false.

subtract(10, 2)                     // 8
subtract(0, 0)                      // 0
subtract(-4, 1)                     // -5
subtract("10", 2)                   // 8
subtract(5, true)                   // false
subtract(true, false)               // false
subtract("Monday", "Tuesday")       // false
subtract()                          // false

10. Write a function named calculateChange that takes in two inputs, totalPaid and totalCost. If both inputs are numeric or numeric strings, calculateChange should return the change after subtracting the cost from the amount paid. The return should be in $x.xx format as a string Note: it should return with two decial places. If either or both inputs are not numeric or numeric strings, calculateChange should return false.

calculateChange(7.50, 1.50)         // $6.00
calculateChange(10, 5)              // $5.00
calculateChange("100", 50)          // $50.00
calculateChange(10, true)           // false
calculateChange([1, 2, 3], 10)      // false
calculateChange("Codeup", 100)      // false
calculateChange()                   // false

Testing your work w/ automated tests

Open assessment.html in your browser. Jasmine will run tests on the code inside solutions.js. The first time you load assessment.html, you will see every test failing because solutions.js is empty to start.

The automated tests provide immediate feedback as to whether or not your solutions solve the problems.

• Click on Spec List inside of assessment.html to see test results.

• If all the specs for isNegative function are green, then the provided solution is correct.

• Make sure that the functions inside solutions.js are not wrapped in an IFFE.

Hints

• If you have green tests and notice that everything is now completely red, it means you likely have a syntax error or a type error in your code. Those kinds of errors will keep all the code from executing properly.

• If you have a syntax error, type error, or reference error in a particular solution function, and it's time to commit and push your work, then comment out that function or the line of code with the error so that your other solutions will be appropriately graded.

• Consider this problem:

Write a function called isBoolean that takes in a value and returns true or false if the argument provided is a boolean data-type or not.

isBoolean("Dog") should return false because a string is not a boolean

isBoolean(false) should return true because only true and false are boolean values.

• When a problem says return, it means return, not console.log.

• When a problem says that a function will take in an input, then it means the function must be defined so that it takes in an argument as its input, rather than relying on variables defined outside the function.

The following example is incorrect because the function does not take in an argument. It's modifying a global variable, and that is not the same as accepting an input as an argument.

var input = "Grace Hopper"
function isBoolean() {
    return typeof input == "boolean";
}

This is incorrect because the function doesn't return the output. Functions that do not have an explicit return statement return undefined by default.

function isBoolean(input) {
    console.log(typeof input == 'boolean');
}

Correct solution:

function isBoolean(input) {
    return typeof input == "boolean";
}