Array.sortInPlaceBy<'T,'Key> Function (F#)

Sorts the elements of an array by mutating the array in place, using the given projection for the keys. Elements are compared using

Namespace/Module Path: Microsoft.FSharp.Collections.Array

Assembly: FSharp.Core (in FSharp.Core.dll)

// Signature:
Array.sortInPlaceBy : ('T -> 'Key) -> 'T [] -> unit (requires comparison)

// Usage:
Array.sortInPlaceBy projection array


  • projection
    Type: 'T -> 'Key

    The function to transform array elements into the type that is compared.

  • array
    Type: 'T[]

    The input array.


This is not a stable sort, that is, the original order of equal elements might not be preserved. For a stable sort, consider using Seq.sort.

This function is named SortInPlaceBy in compiled assemblies. If you are accessing the function from a language other than F#, or through reflection, use this name.


The following code illustrates the use of Array.sortInPlaceBy.

let array1 = [|1; 4; 8; -2; 5|]
Array.sortInPlaceBy (fun elem -> abs elem) array1
printfn "%A" array1


[|1; -2; 4; 5; 8|]


Windows 8, Windows 7, Windows Server 2012, Windows Server 2008 R2

Version Information

F# Core Library Versions

Supported in: 2.0, 4.0, Portable

See Also


Collections.Array Module (F#)

Microsoft.FSharp.Collections Namespace (F#)