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abdirahman liban
Courses Plus Student 2,163 PointsVariadic Parameters
I wrote this code in xcode :
func mean (numbers:Double...)-> Double {
var total : Double = 0
for number in numbers {
total += numbers
}
return total / Double(numbers.count)
}
but is show me this error : binary operator "+=" cannot be applied to operands of type double and double
3 Answers
Greg Kaleka
39,018 PointsCareful with that error message - I imagine it's actually telling you it can't apply += to operands of type Double and [Double], because you're trying to add the whole numbers array!
You want total += number, not total += numbers.
Cindy Lea
Courses Plus Student 6,485 PointsTry doing it the long way to see if it works: total = total + numbers
abdirahman liban
Courses Plus Student 2,163 Pointsit show me error : cannot convert value of type '[Double]' to expected argument type 'Double'
Greg Kaleka
39,018 PointsYep - that error is telling you exactly what you need to know. You can't convert an array of Doubles into a Double. That's what [Double] is - an array of Doubles.
Cindy Lea
Courses Plus Student 6,485 PointsTry this:
total += Double(numbers)
abdirahman liban
Courses Plus Student 2,163 Pointsit show me error : cannot invoke intializer for type 'Double' for type 'Double ' with an argument list of '((Double))'
abdirahman liban
Courses Plus Student 2,163 Pointsabdirahman liban
Courses Plus Student 2,163 Pointsthank you