MoreEnumerable.Scan<TSource> Method (IEnumerable<TSource>, Func<TSource, TSource, TSource>) |
Peforms a scan (inclusive prefix sum) on a sequence of elements.
Namespace: MoreLinq
Assembly: MoreLinq (in MoreLinq.dll) Version: 2.7.0
Syntaxpublic static IEnumerable<TSource> Scan<TSource>( this IEnumerable<TSource> source, Func<TSource, TSource, TSource> transformation )
Parameters
- source
- Type: System.Collections.Generic.IEnumerable<TSource>
Source sequence - transformation
- Type: System.Func<TSource, TSource, TSource>
Transformation operation
Type Parameters
- TSource
- Type of elements in source sequence
Return Value
Type: IEnumerable<TSource>The scanned sequence
Usage Note
In Visual Basic and C#, you can call this method as an instance method on any object of type IEnumerable<TSource>. When you use instance method syntax to call this method, omit the first parameter. For more information, see Extension Methods (Visual Basic) or Extension Methods (C# Programming Guide).Remarks
An inclusive prefix sum returns an equal-length sequence where the
N-th element is the sum of the first N input elements. More
generally, the scan allows any commutative binary operation, not
just a sum.
The exclusive version of Scan is PreScan<TSource>(IEnumerable<TSource>, Func<TSource, TSource, TSource>, TSource).
This operator uses deferred execution and streams its result.
ExamplesFunc<int, int, int> plus = (a, b) => a + b; int[] values = { 1, 2, 3, 4 }; IEnumerable<int> prescan = values.PreScan(plus, 0); IEnumerable<int> scan = values.Scan(plus; a + b); IEnumerable<int> result = values.ZipShortest(prescan, plus);
See Also