Class SlidingWindowExtensions

Provides extension method for sliding window transformation of a collection.

Inheritance

System.Object

SlidingWindowExtensions

Inherited Members

System.Object.ToString()

System.Object.Equals(System.Object)

System.Object.Equals(System.Object, System.Object)

System.Object.ReferenceEquals(System.Object, System.Object)

System.Object.GetHashCode()

System.Object.GetType()

System.Object.MemberwiseClone()

Namespace: Scaleout.Streaming.TimeWindowing.Linq

Assembly: Scaleout.Streaming.TimeWindowing.dll

Syntax

public static class SlidingWindowExtensions

Methods

ToSlidingWindows<TSource>(IEnumerable<TSource>, Func<TSource, DateTime>, DateTime, DateTime, TimeSpan, TimeSpan)

Transforms a collection into an enumerable collection of sliding windows. The source collection must be sorted chronologically.

Declaration

public static IEnumerable<ITimeWindow<TSource>> ToSlidingWindows<TSource>(this IEnumerable<TSource> source, Func<TSource, DateTime> timestampSelector, DateTime startTime, DateTime endTime, TimeSpan windowDuration, TimeSpan every)

Parameters

Type	Name	Description
System.Collections.Generic.IEnumerable<TSource>	source	The sequence of elements to transform.
System.Func<TSource, System.DateTime>	timestampSelector	A function to extract a timestamp from an element.
System.DateTime	startTime	Start time (inclusive) of the first sliding window.
System.DateTime	endTime	End time (exclusive) for the last of sliding window(s).
System.TimeSpan	windowDuration	Duration of each time window. This is a maximum value that will be shortened for the last window(s) in the returned sequence (see remarks).
System.TimeSpan	every	The period of time between the start of each sliding window.

Returns

Type	Description
System.Collections.Generic.IEnumerable<ITimeWindow<TSource>>	An enumerable set of ITimeWindow<TElement> collections.

Type Parameters

Name	Description
TSource	The type of objects in the source collection.

Remarks

The method returns a sequence of overlapping ITimeWindow<TElement> elements, where each window is an enumerable collection of elements from the source collection whose timestamp falls within its specified range. The StartTime is inclusive and the EndTime is exclusive.

The last sliding windows returned by this method may have a shorter duration than what is specified by the windowDuration argument. This happens when the duration would cause the window to extend beyond the specified endTime. These trailing windows can be skipped by using a Linq Where() operation on the returned sequence to filters out windows with short durations.