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iOS Swift 2.0 Functions Function Parameters Returning Complex Values

Sheng Wei
Sheng Wei
4,382 Points
Posted by Sheng Wei
Sheng Wei
4,382 Points

[Help!] Function with Switch statements, tuples and return values

Task: Declare a function named getTowerCoordinates that takes a single parameter of type String, named location, and returns a tuple containing two Double values. Use a switch statement to switch on the string passed in to return the right set of coordinate values for the location.

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

Input: "Eiffel Tower" Desired Function Output: (48.8582, 2.2945)

I think my real problem is that Im not sure which terms initialise, switch and return. Would really appreciate any help!

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

    var location: String,lat: Double,lon: Double

    switch (location) {

    case "Eiffel Tower": return(48.8582, 2.2945)
    case "Great Pyramid": return(29.9792, 31.1344)
    case "Sydney Opera House": return(33.8587, 151.2140)

    default: location = "Dont know"

    }

    return (lat, lon)

}

1 Answer

Anjali Pasupathy
Anjali Pasupathy
28,883 Points
Anjali Pasupathy
Anjali Pasupathy
28,883 Points

You only have to make a few changes.

The challenge won't accept a named tuple for the return value, so you need to change "(lat: Double, lon: Double)" to "(Double, Double)" in the function header.

You don't need the first line of code inside your function ("var location: String,lat: Double,lon: Double"), so you can delete that.

Inside the switch statement, you need to change the format of your default case - the challenge asks you to return (0, 0) for the default case, so you should replace that line with "default: return (0, 0)".

After that change is made, you don't need the last line of code inside your function ("return (lat, lon)"), so you can delete that.

func getTowerCoordinates (location: String) -> (lat: Double, lon: Double) { // CHANGE RETURN VALUE TO (Double, Double)

    var location: String,lat: Double,lon: Double // DELETE THIS LINE

    switch (location) {

    case "Eiffel Tower": return(48.8582, 2.2945)
    case "Great Pyramid": return(29.9792, 31.1344)
    case "Sydney Opera House": return(33.8587, 151.2140)

    default: location = "Dont know" // CHANGE DEFAULT STATEMENT TO return (0, 0)

    }

    return (lat, lon) // DELETE THIS LINE

}

I hope this helps!

Sheng Wei
Sheng Wei
4,382 Points
Sheng Wei
Sheng Wei
4,382 Points

Thanks Anjali, couldn't have asked for a better answer! :)