Multiplying variables and doubles in swift

2 Solutions Collect From Internet About “Multiplying variables and doubles in swift”

You can only multiple two of the same data type.

var billBeforeTax = 100 // Interpreted as an Integer
var taxPercentage = 0.12 // Interpreted as a Double
var tax = billBeforeTax * taxPercentage // Integer * Double = error

If you declare billBeforeTax like so..

var billBeforeTax = 100.0

It will be interpreted as a Double and the multiplication will work. Or you could also do the following.

var billBeforeTax = 100
var taxPercentage = 0.12
var tax = Double(billBeforeTax) * taxPercentage // Convert billBeforeTax to a double before multiplying.

You just have to cast your int variable to Double as below:

    var billBeforeTax = 100
    var taxPercentage = 0.12
    var tax = Double(billBeforeTax) * taxPercentage