tijanae/initlab723

initlab723

/*:

Exercise - Structs, Instances, and Default Values

Imagine you are creating some kind of app for monitoring location. Create a GPS struct with two variable properties, latitude and longitude, both with default values of 0.0. */

struct GPS{
var latitude = 0.0
var longitude = 0.0
}

/*: Create a variable instance of GPS called somePlace. It should be initialized without supplying any arguments. Print out the latitude and longitude of somePlace, which should be 0.0 for both. */

var somePlace = GPS()

/*: Change somePlace's latitude to 51.514004, and the longitude to 0.125226, then print the updated values. */

somePlace = GPS(latitude: 51.514004, longitude: 0.125226)
print(somePlace)

/*: Now imagine you are making a social app for sharing your favorite books. Create a Book struct with four variable properties: title, author, pages, and price. The default values for both title and author should be an empty string. pages should default to 0, and price should default to 0.0. */

struct Book{
var title: String = ""
var author: String = ""
var pages: Int = 0
var price: Double = 0.0
}

/*: Create a variable instance of Book called favoriteBook without supplying any arguments. Print out the title of favoriteBook. Does it currently reflect the title of your favorite book? Probably not. Change all four properties of favoriteBook to reflect your favorite book. Then using the properties of favoriteBook, print out facts about the book. */

var favoriteBook = Book()

print(favoriteBook)

favoriteBook = Book(title: "Harry Potter and the Prisoner of Azkaban", author: "J.K. Rowling", pages: 435, price: 21.34)

//: page 1 of 10 | Next: App Exercise - Workout Tracking /*:

App Exercise - Workout Tracking

These exercises reinforce Swift concepts in the context of a fitness tracking app.

Your fitness tracking app wouldn't be much of a fitness tracker if it couldn't help users track their workouts. In order to track a user's run, you'll need to have some kind of data structure that can hold information about the workout. For the sake of simplicity, you'll focus specifically on running workouts.

Create a RunningWorkout struct. It should have variables properties for distance, time, and elevation. All three properties should have default values of 0.0. */

struct RunningWorkout{
var distance = 0.0
var time = 0.0
var elevation = 0.0
}

/*: Create a variable instance of RunningWorkout called firstRun without supplying any arguments. Print out all three properties of firstRun. This is a good example of when using default values is appropriate, seeing as all running workouts start with a distance, time, and elevation change of 0. */

var firstRun = RunningWorkout()

print(firstRun)

/*: Now imagine that throughout the course of the run, you go a distance of 2396 meters in 15.3 minutes, and gain 94 meters of elevation. Update the values of firstRun's properties accordingly. Print a statement about your run using the values of each property. */

firstRun = RunningWorkout(distance: 2396, time: 15.3, elevation: 94)

print(firstRun)

//: Previous | page 2 of 10 | Next: Exercise - Memberwise and Custom Initializers /*:

Exercise - Memberwise and Custom Initializers

If you completed the exercise Structs, Instances, and Default Values, you created a GPS struct with default values for properties of latitude and longitude. Create your GPS struct again, but this time do not provide default values. Both properties should be of type Double. */

struct GPS{
var latitude: Double
var longitude: Double
}

/*: Now create a constant instance of GPS called somePlace, and use the memberwise initializer to set latitude to 51.514004, and longitude to 0.125226. Print the values of somePlace's properties. */

let somePlace = GPS(latitude: 51.514004, longitude: 0.125226)

print(somePlace)

/*: In Structs, Instance, and Default Values, you also created a Book struct. Creat this struct again without default values. Give each property appropriate types. Declare your favoriteBook instance and pass in the values of your favorite book using the memberwise initializer. Print a statement about your favorite book using favoriteBook's properties. */

struct Book{
var title: String
var author: String
var pages: Int
var price: Double
}

let favoriteBook = Book(title: "Kindred", author: "Octavia E. Butler", pages: 264, price: 15.43)

print("My favorite book is by \(favoriteBook.author). It is called \(favoriteBook.title). It is \(favoriteBook.pages) long and is sold for $\(favoriteBook.price)")

/*: Make a Height struct with two variable properties, heightInInches and heightInCentimeters. Both should be of type Double.

Create two custom initializers. One initializer will take a Double argument that represents height in inches. The other initializer will take a Double argument that represents height in centimeters. Each initializer should take the passed in value and use it to set the property that corresponds to the unit of measurement passed in. It should then set the other property by calculating the right value from the passed in value. Hint: 1 inch = 2.54 centimeters.

• Example: If you use the initializer for inches to pass in a height of 65, the initializer should set heightInInches to 65 and heightInCentimeters to 165.1. */

struct Height{
var heightInInches: Double
var heightInCentimeters: Double

init(heightInCentimeters: Double){
self.heightInCentimeters = heightInCentimeters
self.heightInInches = heightInCentimeters / 2.54
}

init(heightInInches: Double){
self.heightInInches = heightInInches
self.heightInCentimeters = heightInInches * 2.54
}

}
var tikiHeight = Height(heightInInches: 67)
print(tikiHeight)

/*: Now create a variable instance of Height called someonesHeight. Use the initializer for inches to set the height to 65. Print out the property for height in centimeters and verify that it is equal to 165.1. */

var someonesHeight = Height(heightInInches: 65)
print(someonesHeight)

/*: Now create a variable instance of Height called myHeight and initialize it with your own height. Verify that both heightInInches and heightInCentimeters are accurate. */

var tikiHeight2 = Height(heightInCentimeters: 170.18)
print(tikiHeight)

//: Previous | page 3 of 10 | Next: App Exercise - Users and Distance /*:

App Exercise - Users and Distance

These exercises reinforce Swift concepts in the context of a fitness tracking app.

For most apps you'll need to have a data structure to hold information about a user. Create a User struct that has properties for basic information about a user. At a minimum, it should have properties to represent a user's name, age, height, weight, and activity level. You could do this by having name be a String, age be an Int, height and weight be of type Double, and activityLevel be an Int that will represent a scoring 1-10 of how active they are. Implement this now. */

struct UserInfo {
var name: String = ""
var age: Int = 0
var height: Double = 0.0
var weight: Double = 0.0
var activityLevel: Int = 0
}

/*:
Create a variable instance of `User` and call it your name. Use the memberwise initializer to pass in information about yourself. Then print out a description of your `User` instance using the instance's properties.
*/
var tiki = UserInfo(name: "Tia Janae", age: 24, height: 5.7, weight: 175, activityLevel: 6)

print(tiki)

/*: In previous app exercises, you've worked with distance in the fitness tracking app example as a simple number. However, distance can be represented using a variety of units of measurement. Create a Distance struct that will represent distance in various units of measurement. At a minimum, it should have a meters property and a feet property. Create a custom initializer corresponding to each property (i.e. if you only have the two properties for meters and feet you will then have two initializers) that will take in a distance in one unit of measurement and assign the correct value to both units of measurements. Hint: 1 meter = 3.28084 feet.

• Example: If you use the initializer for meters and pass in a distance of 1600, the initializer should set meters to 1600 and feet to 5249.344. */

struct Distance {
var meters: Double
var feet: Double

init (meters: Double){
self.meters = meters
self.feet = meters * 3.28084
}

init (feet: Double){
self.feet = feet
self.meters = feet / 3.28084
}
}

/*: Now create an instance of Distance called mile. Use the initializer for meters to set the distance to 1600. Print out the property for feet and verify that it is equal to 5249.344. */

var mile = Distance(meters: 1600)
print(mile)

/*: Now create another instance of Distance and give it some other distance. Ensure that both properties are set correctly. */

var fromHereToTheMoon = Distance(feet: 1261000000)
print(fromHereToTheMoon)

//: Previous | page 4 of 10 | Next: Exercise - Methods /*:

Exercise - Methods

A Book struct has been created for you below. Add an instance method on Book called description that will print out facts about the book. Then create an instance of Book and call this method on that instance. */

//struct Book {
//    var title: String
//    var author: String
//    var pages: Int
//    var price: Double
//}


struct Book {
var title: String
var author: String
var pages: Int
var price: Double

func description(){
print("\(title) was written by \(author) and for the price of \(price), you can go on a \(pages) page journey!")
}
}

var aBook = Book(title: "animal WINGS", author: "Tolate ToQuit", pages: 687, price: 8.99)
print(aBook.description())

/*: A Post struct has been created for you below, representing a generic social media post. Add a mutating method on Post called like that will increment likes by one. Then create an instance of Post and call like() on it. Print out the likes property before and after calling the method to see whether or not the value was incremented. */

struct Post {
var message: String
var likes: Int
var numberOfComments: Int

mutating func like () {
likes += 1
}
}


var igStar = Post(message: "hey hunnies", likes: 50, numberOfComments: 19)

print(igStar.likes)
igStar.like()
print(igStar.likes)

//: Previous | page 5 of 10 | Next: App Exercise - Workout Functions /*:

App Exercise - Workout Functions

These exercises reinforce Swift concepts in the context of a fitness tracking app.

A RunningWorkout struct has been created for you below. Add a method on RunningWorkout called postWorkoutStats that prints out the details of the run. Then create an instance of RunningWorkout and call postWorkoutStats(). */

struct RunningWorkout {
var distance: Double
var time: Double
var elevation: Double

func postWorkoutStats (){
print("Great Job! Your run was \(distance) and completed in \(time) minutes. Your elevation was \(elevation) feet. Look at you! Superhero in the making!")
}
}

var tikiRun = RunningWorkout(distance: 5.9, time: 60, elevation: 120)

tikiRun.postWorkoutStats()

/*: A Steps struct has been created for you below, representing the day's step-tracking data. It has the goal number of steps for the day and the number of steps taken so far. Create a method on Steps called takeStep that increments the value of steps by one. Then create an instance of Steps and call takeStep(). Print the value of the instance's steps property before and after the method call. */

struct Steps {
var steps: Int
var goal: Int

mutating func takeStep (){
steps += 1
}
}

var tikiCommute = Steps(steps: 8000, goal: 10000)
tikiCommute.takeStep()
print(tikiCommute.steps)

//: Previous | page 6 of 10 | Next: Exercise - Computed Properties and Property Observers