comparisons.js

// In the exercises below, write your own code where indicated
// to achieve the desired result.

// One example is already completed. Your task is to complete
// any remaining prompt.

// Make sure to run the file in your command line using `node <filename>.js`


// -------------------
// PART 1: Comparing variables
// -------------------

var numberTeachers = 4
var numberStudents = 20
var stringTeachers = "4"
var numberDogs = 0

// EXAMPLE: log the result of the comparison: is numberTeachers greater than numberStudents?
console.log("Is numberTeachers greater than numberStudents?", numberTeachers > numberStudents);
// this should log: "Is numberTeachers greater than numberStudents?" false

// YOU DO: log the result of the comparison: is numberTeachers less than numberStudents?
console.log("Is numberTeachers less than numberStudents?", numberTeachers < numberStudents);
// this should log: true

// YOU DO: log the result of the comparison: is numberTeachers strictly equal to stringTeachers?
console.log("Is numberTeachers strictly equal to stringTeachers?", numberTeachers === stringTeachers);
// this should log: false

// YOU DO: log the result of the comparison: is numberTeachers not equal to numberStudents?
console.log("Is numberTeachers not equal to numberStudents?", numberTeachers !== numberStudents);
// this should log: true

// YOU DO: log the result of the comparison: is numberStudents greater than or equal to 20?
console.log("Is numberStudents greater than or equal to 20?", numberStudents >= 20);
// this should log: true

// YOU DO: log the result of the comparison: is numberStudents greater than or equal to 21?
console.log("Is numberStudents greater than or equal to 21?", numberStudents >= 21);
// this should log: false

// YOU DO: log the result of the comparison: is numberStudents less than or equal to 20?
console.log("Is numberStudents less than or equal to 20?", numberStudents <= 20);
// this should log: true

// YOU DO: log the result of the comparison: is numberStudents less than or equal to 21?
console.log("Is numberStudents less than or equal to 21?", numberStudents <= 21);
// this should log: true


// #-------------------
// PART 2: Articulating what you are doing
// #-------------------

// For the following prompts, you will be given a line of code and your task is to type out a Comment,
// in English, explaining what that line of code is doing, including what the comparison will evaluate to.
// Be as technically precise as possible, but don't just copy and paste a definition from the readings.
// Make sure YOU can explain it that way!

console.log(4 < 9);
// YOU DO: Explain.
// The console.log is evaluating the question of is 4 less than 9. 
// In this case 4 *is less than 9 so it evaluates to true.

var books = 3;
console.log(4 < books);
// YOU DO: Explain.
// The console log is evaluating the question of is 4 less than assignment operator 'books', which has a value of 3.
// In this case 4 is *not less than 3, so it evaluates to false.

var friends = 6;
var siblings = 2;
console.log(friends > siblings);
// YOU DO: Explain.
// The console log is evaluating whether assignment operator 'friends' is greater than assignment operator 'siblings'.
// 'friends' has a value of 6, and 'siblings has a value of 2.
// In this case 6 *is less than 2, so it evaluates to true.

var attendees = 9;
var meals = 8;
console.log(attendees !== meals);
// YOU DO: Explain.
// The console log is evaluating whether assignment operator 'attendees' is not equal to assignment operator 'meals'.
// 'attendees' has a value of 9, and meals has a value of 8.
// Therefore because 9 and 8 are *not equal, it evaluates to true.

// #-------------------
// PART 3: Logical Operators
// #-------------------

var isHungry = true;
var finishedHomework = false;

// EXAMPLE:
// Determine if the user is hungry and has completed their homework
console.log(isHungry && finishedHomework);
// Determine if the user is hungry or has completed their homework
console.log(isHungry || finishedHomework);

var lovesToPlay = true;
var lovesDogPark = false;
var lovesTreats = true;
var age = 1;

// YOU DO:
// Determine if the dog loves to play and loves treats
console.log(lovesToPlay && lovesTreats);
// True

// Determine if the dog loves to play and loves the dog park
console.log(lovesToPlay && lovesDogPark);
// False

// Determine if the dog loves to play or loves the dog park
console.log(lovesToPlay || lovesDogPark);
//True

// Determine if the dog loves to play and is a puppy
console.log(lovesToPlay && age);

// What did your final line of code evaluate to? 
// Why do you think that is? Explain.
// ANSWER:
// The answer evaluated to 1. Booleans are evaluated based on True / False propositions
// Numbers are evaluated based on comparison operators.

// If we assume that a puppy becomes a junior dog by age 1 then...
console.log(lovesToPlay && age < 1);
// Then the question of whether this dog loves to play and is a puppy? It evaluates to false.