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List.sum<^T> Function (F#)

Den Delimarsky|Last Updated: 8/18/2017
2 Contributors

Returns the sum of the elements in the list.

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

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


// Signature:
List.sum : ^T list -> ^T (requires ^T with static member (+) and ^T with static member Zero)

// Usage:
List.sum list


list Type: ^Tlist

The input list.

Return Value

The sum of all elements of the list.


May throw an OverflowException due to arithmetic overflows.


The elements are summed using the checked + operator and Zero property associated with the summed type.

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


The following code example illustrates the use of List.sum, List.sumBy, and List.average:

// Compute the sum of the first 10 integers by using List.sum.
let sum1 = List.sum [1 .. 10]

// Compute the sum of the squares of the elements of a list by using List.sumBy.
let sum2 = List.sumBy (fun elem -> elem*elem) [1 .. 10]

// Compute the average of the elements of a list by using List.average.
let avg1 = List.average [0.0; 1.0; 1.0; 2.0]

printfn "%f" avg1




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.List Module (F#)

Microsoft.FSharp.Collections Namespace (F#)

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