Doubles to Strings swift

Question

I am trying to convert a double, value to a string. This string will be set as the text of a Cocoa Touch UI element, that only accepts strings (I can't use the double as-is)

let value = example double value (my actual code is not this)
UIElementBeingSet.text = NSString(value)

When I try the above code, I get "Use of unresolved identifier 'value'.

Through my research, I have found questions like this, which seem to be asking similar things, but that question and similar ones involve limiting precision, don't involve UI elememts (which I am asking about), and are just overall not the answers I need.

Sorry for a basic question, and thanks!

For a lot more info on string formatting, see [this thread](http://stackoverflow.com/questions/24051314/precision-string-format-specifier-in-swift/24052438#24052438) — David Berry, Aug 26 '14 at 19:10

zaph · Accepted Answer · 2014-08-26T16:36:33.377

2

To use standard string formatting use format:

let d = 1.0 / 3.0
let s = String(format: "%0.3f", d)
println("s: \(s)")

Output:

s: 0.333

or

let s = String(format: "%0.16f", d)
println("s: \(s)")

Output:

s: 0.3333333333333333

String interpolation does not allow any control over the presentation, it is good for logging but severly lacking for presentation to a user.

edited Aug 26 '14 at 16:36

answered Aug 26 '14 at 16:31

zaph

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score 1 · Answer 2 · answered Aug 26 '14 at 15:11

1

Use string interpolation:

let d: Double = 1 / 3
let x = "\(d)"

If you try that in a playground, it will print:

"0.333333333333333"

Doubles to Strings swift

2 Answers2