Search code examples
decimalswift3nsdecimalnumber

Rounding Decimal

In NSDecimalNumber there's a method to round the number, I.E.

let handler = NSDecimalNumberHandler(roundingMode: .plain, scale: 2, raiseOnExactness: false, raiseOnOverflow: false, raiseOnUnderflow: false, raiseOnDivideByZero: false)

let example: NSDecimalNumber = 1.345
let rounded: NSDecimalNumber = example.rounding(accordingToBehavior: handler)

Now I've switched to Decimal and it doesn't seem to have the method to round the number like NSDecimalNumber has. Should I cast it to NSDecimalNumber and cast it back to Decimal just to round things up or is there a better and more elegant way of rounding a Decimal?

EDIT: made a better example

Solution

  • Decimal has become an easy and concise way to handle decimal numbers in Swift 3, but if you want to control some rounding mode or rounding scale, you need to use NSDecimal... functions.

    Foundation Functions

    See Decimals part.

    NSDecimalRound(_:_:_:_:)

    var dexample: Decimal = 1.345
var drounded: Decimal = Decimal()
NSDecimalRound(&drounded, &dexample, 2, .plain)
print(drounded) //->1.35