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iOS Swift 2.0 Functions Function Parameters Returning Complex Values

Posted by Billy Potts
Billy Potts
Courses Plus Student 2,344 Points

I'm having trouble with this function

when the function is done your supposed to be able to call the function and add in the string name to get the lat, lon

functions.swift 
// Enter your code below
func getTowerCoordinates( var location: String) -> (Double, Double) {
     switch location {
     case "Eiffel Tower": lat, lon = (48.8582, 2.2945)
     case "Great Pyramid": lat, lon = (29.9792, 31.1344)
     case "Sydney Opera House": lat, lon = (33.8587, 151.2140)
     default location: (0, 0)
      }
      return location
}

3 Answers

jcorum
jcorum
71,830 Points
jcorum
jcorum
71,830 Points

Very close, but you need to return the lat and lon:

// Enter your code below
func getTowerCoordinates( var location: String) -> (Double, 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: 
      return (0, 0)
      }  
}
Angel Caro
Angel Caro
11,831 Points
Angel Caro
Angel Caro
11,831 Points

The return type does not need parameter names and you don't declare a var in a parameter and you don't return location, you need to refactor your code like this:

func getTowerCoordinates(location: String) -> (Double, 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:
        return (0, 0)
    }

}
Billy Potts
Billy Potts
Courses Plus Student 2,344 Points

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).

thats the task i did the function how you said and its not working

jcorum
jcorum
71,830 Points
jcorum
jcorum
71,830 Points

If you try running your code and then click the Preview button you will see the following:

swift_lint.swift:6:30: error: consecutive statements on a line must be separated by ';'
     case "Eiffel Tower": lat, lon = (48.8582, 2.2945)
                             ^
                             ;
swift_lint.swift:6:30: error: expected expression
     case "Eiffel Tower": lat, lon = (48.8582, 2.2945)
                             ^
swift_lint.swift:7:31: error: consecutive statements on a line must be separated by ';'
     case "Great Pyramid": lat, lon = (29.9792, 31.1344)
                              ^
                              ;
swift_lint.swift:7:31: error: expected expression
     case "Great Pyramid": lat, lon = (29.9792, 31.1344)
                              ^
swift_lint.swift:8:36: error: consecutive statements on a line must be separated by ';'
     case "Sydney Opera House": lat, lon = (33.8587, 151.2140)
                                   ^
                                   ;
swift_lint.swift:8:36: error: expected expression
     case "Sydney Opera House": lat, lon = (33.8587, 151.2140)
                                   ^
swift_lint.swift:9:14: error: expected ':' after 'default'
     default location: (0, 0)
             ^
swift_lint.swift:9:22: error: consecutive statements on a line must be separated by ';'
     default location: (0, 0)
                     ^
                     ;
swift_lint.swift:9:22: error: expected expression
     default location: (0, 0)
                     ^
swift_lint.swift:6:27: error: use of unresolved identifier 'lat'
     case "Eiffel Tower": lat, lon = (48.8582, 2.2945)
                          ^
swift_lint.swift:7:28: error: use of unresolved identifier 'lat'
     case "Great Pyramid": lat, lon = (29.9792, 31.1344)
                           ^
swift_lint.swift:8:33: error: use of unresolved identifier 'lat'
     case "Sydney Opera House": lat, lon = (33.8587, 151.2140)
                                ^
swift_lint.swift:9:14: error: expression resolves to an unused l-value
     default location: (0, 0)
             ^~~~~~~~
swift_lint.swift:11:14: error: cannot convert return expression of type 'String' to return type '(Double, Double)'
      return location
             ^~~~~~~~

As we said earlier, you must return a tuple containing the lat and lon values, and here return means a return statement.