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iOS

Still having problems with Fahrenheit to Celsius conversion.

I am getting an error that reads <EXPR>:13:29: error: cannot invoke '-' with an argument list of type '(($T4), ($T8))'

var fahrenheit = 10 var celsius :Double = (5/9) * (fahrenheit - 32) <--- The error is on this line fahrenheit

I basically want to transform fahrenheit to celsius using this for swift. At this point i am not sure what i am doing wrong.

2 Answers

since fahrenheit and 32 are ints, you need to cast the subtraction to a double:

var fahrenheit = 10
var celsius :Double = (5/9) * Double(fahrenheit - 32)

Alright this worked thanks!

no problem. one way to avoid the cast would be to just to use doubles throughout your code:

var fahrenheit = 10.0
var celsius = (5.0/9.0) * (fahrenheit - 32.0)