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iOS Functions in Swift Adding Power to Functions Returning Complex Values

Daneil Chen
Daneil Chen
1,768 Points
Posted by Daneil Chen
Daneil Chen
1,768 Points

what's wrong

In this challenge, we have the following geographical coordinates

Eiffel Tower - lat: 48.8582, lon: 2.2945 Great Pyramid - lat: 29.9792, lon: 31.1344 Sydney Opera House - lat: 33.8587, lon: 151.2140

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)

functions.swift 
// Enter your code below
func coordinates(location: String) -> (Double, Double) {

    var lat: Double = 0.0, lon: Double = 0.0

    switch location {
    case "Eiffel Tower": lat = 48.8582; lon = 2.2945
    case "Great Pyramid": lat = 29.9792; lon = 31.1344
    case "Sydney Opera House": lat = 33.8587;  lon = 151.2140
    default: return (0,0)
    }
    return (lat, lon)
}
print(coordinates(location: "Eiffel Tower"))

2 Answers

Daneil Chen
Daneil Chen
1,768 Points
Daneil Chen
Daneil Chen
1,768 Points

I think the result does not match very well because of double type

Matt Skelton
Matt Skelton
4,548 Points
Matt Skelton
Matt Skelton
4,548 Points

Hey Daneil,

You've almost got it, the challenge asks that you also declare an external name of "for" to the parameter of your coordinates method, as well as the internal name of "location".

First, you'll need to tweak the signature of your method to include this external name. Then you'll have to use the external name when you call the method.

func coordinates(for location: String) -> (Double, Double) {
   ...
}
print(coordinates(for: "Eiffel Tower"))

Hope this helps!