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iOS Swift 2.0 Functions Function Parameters Returning Complex Values

isaac brakha
isaac brakha
6,781 Points
Posted by isaac brakha
isaac brakha
6,781 Points

Hello, why is my code challenge wrong? (functions course)

this is the objective, thank you in advance.

For this challenge, let's say we're building a component of an app that allows a user to type in a location of a famous landmark and get back the geographical coordinates.

To keep the scope limited, let's say we're only working with the following values.

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 getTowerCoordinates that takes a single parameter of type String, named location, and returns a tuple containing two Double values (Note: You do not have to name the return values)

Use a switch statement to switch on the string passed in to return the right set of coordinate values for the location.

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.

For the default case in the switch statement, return (0,0)

functions.swift 
// Enter your code below
func getTowerCoordinates(location: String) -> (lat: Double, lon: Double) {
  var lat: Double
  var lon: Double
  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: 0.0;0.0
  } 
  return (lat, lon)

}
Brian Bangma
Brian Bangma
1,514 Points
Brian Bangma
Brian Bangma
1,514 Points

Same issue for me. Even with the above code, which works in a playground, it does not pass the challenge. The code produces a tuple but the challenge says it does not.

2 Answers

Pavel Fomchenkov
Pavel Fomchenkov
20,897 Points
Pavel Fomchenkov
Pavel Fomchenkov
20,897 Points

Your lat and lon variables do not get initialized (ever assigned any value) before the return statement in the default case (because they are just left var'ed and are not assigned to anything later). Initialize them to 0.0 at the declaration stage (var lat = 0.0) and just don't do anything in the default case (you cannot omit this case itself, so just don't do anything inside it like that: default: break) or print some useful message with default: print("Unknown town, Isaac!").

Or just set them both to 0.0 in this case. Almost forgot about his opportunity.

Janam Dave
Janam Dave
1,683 Points
Janam Dave
Janam Dave
1,683 Points

I had the same problem, it really frustrated me. I went back to read the directions and they say you don't need to name the parameters of which you will return values of type Double. So, completely take out the variables lon and lat from your declaration and just simply say func getTowerLocation(Location: String) -> (Double, Double) {

Then, In your case statements, just return the appropriate longitude and latitude values instead of setting them equal to specific numbers. You have to do all this because of that piece in the directions, you're not wrong here (and your way works) it's just the problem can't check your answer correctly unless you do it this way, for some very stupid reason.