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iOS Functions in Swift Adding Power to Functions Returning Complex Values

Posted by pogtynmsax
pogtynmsax
4,083 Points

How to declare a function named coordinates with single parameter of type String, returns tuple of two Double values...?

how to declare a function named coordinates with single parameter of type String, returns tuple of two Double values, the return value does not have to be named. For example: If I use your function and pass in the String "Eiffel Tower" as an argument. I should get (48.8582, 2.2945) as the value. If a string is passed in that does not match the set above, return (0,0).

functions.swift 
// Enter your code below
func coordinates (for location: String)-> (Double, Double) {
      var lat = 0.0
      var lon = 0.0
      switch location {
        case "Eiffel Tower":
          lat = 48.8582
          lon = 2.2945
        case "Great Pyramids":
          lat = 29.9792
          lon = 31.1344
        case "Sydney Opera House":
          lat = 33.8587
          lon = 151.2140
        default:
          lat = 0.0
          lon = 0.0
      }  
      return (lat, lon)
}
var locationOf = coordinates (for: "Eiffel Tower")

2 Answers

Alex Souto-Maior
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.a{fill-rule:evenodd;}techdegree
Alex Souto-Maior
iOS Development Techdegree Student 4,909 Points
Alex Souto-Maior
.a{fill-rule:evenodd;}techdegree
Alex Souto-Maior
iOS Development Techdegree Student 4,909 Points

Hey Dawry,

You created two parameters of type Double. This challenge is asking for you to return a tuple of two Double values.

So you should create a parameter of type tuple to begin with.

Here's a suggestion of how the first few lines could start...

func coordinates(for location: String) -> (Double, Double) {

var locationCoordinates: (Double, Double) = (0, 0)

switch location {
    case "Eiffel Tower": locationCoordinates = (48.8582, 2.2945)

etc...

Micah Doulos
Micah Doulos
17,663 Points
Micah Doulos
Micah Doulos
17,663 Points

Alex your comment is inconsistent with the directions.

"Declare a function named coordinates that takes a single parameter of type String, with an external name for, a local name of location, and returns a tuple containing two Double values (Note: You do not have to name the return values). For example, if I use your function and pass in the string "Eiffel Tower" as an argument, I should get (48.8582, 2.2945) as the value. If a string is passed in that doesn’t match the set above, return (0,0)"

Alex Souto-Maior
seal-mask
.a{fill-rule:evenodd;}techdegree
Alex Souto-Maior
iOS Development Techdegree Student 4,909 Points
Alex Souto-Maior
.a{fill-rule:evenodd;}techdegree
Alex Souto-Maior
iOS Development Techdegree Student 4,909 Points

Hi Micah,

I don't understand what you see as an inconsistency.

This is the solution I used. It meets the requirements and passes the code challenge. If you have any questions feel free to reach out.

func coordinates(for location: String) -> (Double, Double) {

var locationCoordinates: (Double, Double) = (0, 0)

switch location {
    case "Eiffel Tower": locationCoordinates = (48.8582, 2.2945)
    case "Great Pyramid": locationCoordinates = (29.9792, 31.1344)
    case "Sydney Opera House": locationCoordinates = (33.8587, 151.2140)
    default: locationCoordinates = (0, 0)
}

return locationCoordinates

}

let location = coordinates(for: "Sydney Opera House")

JUN MENG
JUN MENG
10,249 Points
JUN MENG
JUN MENG
10,249 Points

func coordinates (for location: String) -> (Double, Double) {

var spot: (Double, Double) = (0, 0)

switch location {

case "Eiffel Tower": spot = (48.8582, 2.2945) case "Great Pyramid": spot = (29.9792, 31.1344) case "Sydney Opera House": spot = (33.8587, 151.2140) default: spot = (0.0, 0.0)

} return spot } var locationOF = coordinates (for: "Eiffel Tower")