How to get the integer part and fractional part of a number in Swift - swift

Question

This is a super basic question, but, I can't seem to find an answer in Swift.
Question:
How do I get the whole integer part and fractional part (to the left and right of the decimal point respectively) of a number in Swift 2 and Swift 3? For example, for the number 1234.56789 —
How do I get the integer part 1234.56789 ?
How do I get the fractional part 1234.56789 ?

Answer 1

You could do simple floor and truncating:
let value = 1234.56789
let double = floor(value) // 1234.0
let integer = Int(double) // 1234
let decimal = value.truncatingRemainder(dividingBy: 1) // 0.56789

Answer 2

No need for extensions. Swift already has built in function for this.
let aNumber = modf(3.12345)
aNumber.0 // 3.0
aNumber.1 // 0.12345

Answer 3

Swift 4.xm, 5.x complete solution:
I credit #Thomas solution also I'd like to add few things which allow us to use separated parts in 2 string part.
Especially when we want to use 2 different UILabel for main and decimal part of the number.
Extension below is also managing number quantity of decimal part. I thought it might be useful.
UPDATE: Now, it is working perfectly with negative numbers as well!
public extension Double{
func integerPart()->String{
let result = floor(abs(self)).description.dropLast(2).description
let plusMinus = self < 0 ? "-" : ""
return plusMinus + result
}
func fractionalPart(_ withDecimalQty:Int = 2)->String{
let valDecimal = self.truncatingRemainder(dividingBy: 1)
let formatted = String(format: "%.\(withDecimalQty)f", valDecimal)
let dropQuantity = self < 0 ? 3:2
return formatted.dropFirst(dropQuantity).description
}

Answer 4

Convert your number into String later separate string from .
Try this:-
let number:Float = 123.46789
let numberString = String(number)
let numberComponent = numberString.components(separatedBy :".")
let integerNumber = Int(numberComponent [0])
let fractionalNumber = Int(numberComponent [1])

Answer 5

You could do this ->
let x:Double = 1234.5678
let y:Double = Double(Int(x))
let z:Double = x - Double(Int(x))
print("\(x) \(y) \(z)")
Where x is your original value. y is the integer part and z is the fractional part.
Edit
Thomas answer is the one you want ...

Answer 6

This will definitely work for you in swift 5 and 4
let number = 3.145443
let integerValue = String(format: "%.0f", number)
let integerValue1 = String(format: "%.1f", number)
let integerValue2 = String(format: "%.2f", number)
print(integerValue)
print(integerValue1)
print(integerValue2)
//Output
3
3.1
3.14

Answer 7

modf() works bad with numbers > 1 billion
#Trevor behaves like modf()
#Andres Cedronius example behaves like modf() too (i tried modify it)
#Irshad Ahmed solution is nice
there is some convenience convertions
For some reason you need more control, check out https://developer.apple.com/documentation/foundation/numberformatter
extension Double {
/// 1.00234 -> 1.0
var integerPart: Double {
return Double(Int(self))
}
/// 1.0012 --> 0.0012
var fractionPart: Double {
let fractionStr = "0.\(String(self).split(separator: ".")[1])"
return Double(fractionStr)!
}
/// 1.0012 --> "0.0012"
var fractionPartString: String {
return "0.\(String(self).split(separator: ".")[1])"
}
/// 1.0012 --> 12
var fractionPartInteger: Int {
let fractionStr = "\(String(self).split(separator: ".")[1])"
return Int(fractionStr)!
}
}
print(1000.0.integerPart) // 1000.0
print(1000.0.fractionPart) // 0.0
print(1000.1.integerPart) // 1000.0
print(1000.2.fractionPart) // 0.2
print(1_000_000_000.1.integerPart) // 1000000000.0
print(100_000_000.13233.fractionPart) // 0.13233

Answer 8

var specimen0:Double = 1234.56789
var significant0 = Double.IntegerLiteralType(specimen0) // result is an integer
var fractionals0 = specimen0 - Double(significant0)
var specimen1:Float = -1234.56789
var significant1 = Float.IntegerLiteralType(specimen1) // result is an integer
var fractionals1 = specimen1 - Float(significant1)
var specimen2:CGFloat = -1234.56789
var significant2 = CGFloat.IntegerLiteralType(specimen2) // result is an integer
var fractionals2 = specimen2 - CGFloat(significant2)
These are all built in as of Swift 5.3, I am sure even earlier...