Extreme Optimization™: Complexity made simple.

Math and Statistics
Libraries for .NET

  • Home
  • Features
    • Math Library
    • Vector and Matrix Library
    • Statistics Library
    • Performance
    • Usability
  • Documentation
    • Introduction
    • Math Library User's Guide
    • Vector and Matrix Library User's Guide
    • Data Analysis Library User's Guide
    • Statistics Library User's Guide
    • Reference
  • Resources
    • Downloads
    • QuickStart Samples
    • Sample Applications
    • Frequently Asked Questions
    • Technical Support
  • Blog
  • Order
  • Company
    • About us
    • Testimonials
    • Customers
    • Press Releases
    • Careers
    • Partners
    • Contact us
Introduction
Deployment Guide
Configuration
Using Parallelism
Expand Mathematics Library User's GuideMathematics Library User's Guide
Expand Vector and Matrix Library User's GuideVector and Matrix Library User's Guide
Expand Data Analysis Library User's GuideData Analysis Library User's Guide
Expand Statistics Library User's GuideStatistics Library User's Guide
Expand Data Access Library User's GuideData Access Library User's Guide
Expand ReferenceReference
  • Extreme Optimization
    • Features
    • Solutions
    • Documentation
    • QuickStart Samples
    • Sample Applications
    • Downloads
    • Technical Support
    • Download trial
    • How to buy
    • Blog
    • Company
    • Resources
  • Documentation
    • Introduction
    • Deployment Guide
    • Configuration
    • Using Parallelism
    • Mathematics Library User's Guide
    • Vector and Matrix Library User's Guide
    • Data Analysis Library User's Guide
    • Statistics Library User's Guide
    • Data Access Library User's Guide
    • Reference
  • Reference
    • Extreme
    • Extreme.Collections
    • Extreme.Data
    • Extreme.Data.Json
    • Extreme.Data.Matlab
    • Extreme.Data.R
    • Extreme.Data.Stata
    • Extreme.Data.Text
    • Extreme.DataAnalysis
    • Extreme.DataAnalysis.Linq
    • Extreme.Mathematics
    • Extreme.Mathematics.Algorithms
    • Extreme.Mathematics.Calculus
    • Extreme.Mathematics.Calculus.OrdinaryDifferentialEquations
    • Extreme.Mathematics.Curves
    • Extreme.Mathematics.Curves.Nonlinear
    • Extreme.Mathematics.Distributed
    • Extreme.Mathematics.Distributed.Cuda
    • Extreme.Mathematics.EquationSolvers
    • Extreme.Mathematics.FSharp
    • Extreme.Mathematics.Generic
    • Extreme.Mathematics.Generic.LinearAlgebra
    • Extreme.Mathematics.Generic.LinearAlgebra.Implementation
    • Extreme.Mathematics.Generic.LinearAlgebra.Providers
    • Extreme.Mathematics.Generic.SignalProcessing
    • Extreme.Mathematics.Implementation
    • Extreme.Mathematics.LinearAlgebra
    • Extreme.Mathematics.LinearAlgebra.Complex
    • Extreme.Mathematics.LinearAlgebra.Complex.Decompositions
    • Extreme.Mathematics.LinearAlgebra.Implementation
    • Extreme.Mathematics.LinearAlgebra.IO
    • Extreme.Mathematics.LinearAlgebra.IterativeSolvers
    • Extreme.Mathematics.LinearAlgebra.IterativeSolvers.Preconditioners
    • Extreme.Mathematics.LinearAlgebra.Providers
    • Extreme.Mathematics.LinearAlgebra.Sparse
    • Extreme.Mathematics.Optimization
    • Extreme.Mathematics.Optimization.Genetic
    • Extreme.Mathematics.Optimization.LineSearches
    • Extreme.Mathematics.Random
    • Extreme.Mathematics.SignalProcessing
    • Extreme.Numerics.FSharp
    • Extreme.Statistics
    • Extreme.Statistics.Distributions
    • Extreme.Statistics.IO
    • Extreme.Statistics.Linq
    • Extreme.Statistics.Multivariate
    • Extreme.Statistics.Random
    • Extreme.Statistics.Tests
    • Extreme.Statistics.TimeSeriesAnalysis
  • Extreme.DataAnalysis
    • Accumulator Class
    • Aggregator(T, U) Class
    • Aggregator2(T, U) Class
    • Aggregator2Group Class
    • Aggregator2Group(T) Class
    • AggregatorGroup Class
    • AggregatorGroup(T) Class
    • Aggregators Class
    • BoundaryIntervalBehavior Enumeration
    • CategoricalEncoding Class
    • DataFrame Class
    • DataFrame(R, C) Class
    • DataFrameRow(R, C) Class
    • DateTimeExtensions Class
    • DateTimeUnit Enumeration
    • Direction Enumeration
    • Grouping Class
    • Grouping(TKey) Class
    • Histogram Class
    • Histogram(T) Class
    • IAccumulator(T, U) Interface
    • IAccumulator2(T, U) Interface
    • IAccumulator2(T, U, V) Interface
    • IAggregator Interface
    • IAggregator(T) Interface
    • IAggregator2 Interface
    • IAggregator2(T) Interface
    • IDataFrame Interface
    • IGrouping Interface
    • IIndex Interface
    • Index Class
    • Index(T) Class
    • IntervalIndex(T) Class
    • IPivot Interface
    • JoinIndex Class
    • JoinType Enumeration
    • MissingValueAction Enumeration
    • MissingValueException Class
    • MultipleMissingValueAction Enumeration
    • Pivot Class
    • Pivot(R, C) Class
    • RankTiebreaker Enumeration
    • Recurrence Class
    • SortOrder Enumeration
    • SpecialBins Enumeration
    • Subset Class
    • TypePreservingAggregatorGroup Class
    • VectorExtensions Class
  • Grouping Class
    • Methods
  • Methods
    • ByQuantile Method Overloads
    • ByValue Method Overloads
    • ExpandingWindow Method Overloads
    • Group Method Overloads
    • Partition Method Overloads
    • Pivot(R, C) Method
    • RangeWindow Method Overloads
    • Resample Method Overloads
    • VariablePartition(T) Method
    • VariableWindow(T) Method
    • Window Method Overloads
  • Group Method Overloads
    • Group(T) Method (IEnumerable(T))
    • Group(T) Method (IList(T))
    • Group(T) Method (IEnumerable(T), IEqualityComparer(T))
    • Group(T) Method (IList(T), IEqualityComparer(T))
  • Group(T) Method (IList(T), IEqualityComparer(T))
GroupingGroupT Method (IListT, IEqualityComparerT)Extreme Optimization Numerical Libraries for .NET Professional
Returns a grouping by the unique elements in a list using the specified comparer to determine equality.

Namespace: Extreme.DataAnalysis
Assembly: Extreme.Numerics.Net40 (in Extreme.Numerics.Net40.dll) Version: 6.0.16073.0 (6.0.16312.0)
Syntax

C#
VB
C++
F#
Copy
public static Grouping<T> Group<T>(
	this IList<T> keys,
	IEqualityComparer<T> comparer
)
<ExtensionAttribute>
Public Shared Function Group(Of T) ( 
	keys As IList(Of T),
	comparer As IEqualityComparer(Of T)
) As Grouping(Of T)
public:
[ExtensionAttribute]
generic<typename T>
static Grouping<T>^ Group(
	IList<T>^ keys, 
	IEqualityComparer<T>^ comparer
)
[<ExtensionAttribute>]
static member Group : 
        keys : IList<'T> * 
        comparer : IEqualityComparer<'T> -> Grouping<'T> 

Parameters

keys
Type: System.Collections.GenericIListT
A list.
comparer
Type: System.Collections.GenericIEqualityComparerT
The comparer used to determine whether two keys are equal.

Type Parameters

T
The type of the elements of the list.

Return Value

Type: GroupingT
A grouping of the elements of keys and indexed by the unique elements in keys.

Usage Note

In Visual Basic and C#, you can call this method as an instance method on any object of type IListT. 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).
Version Information

Numerical Libraries

Supported in: 6.0
See Also

Reference

Grouping Class
Group Overload
Extreme.DataAnalysis Namespace

Copyright (c) 2004-2016 ExoAnalytics Inc.

Send comments on this topic to support@extremeoptimization.com

Copyright © 2004-2018, Extreme Optimization. All rights reserved.
Extreme Optimization, Complexity made simple, M#, and M Sharp are trademarks of ExoAnalytics Inc.
Microsoft, Visual C#, Visual Basic, Visual Studio, Visual Studio.NET, and the Optimized for Visual Studio logo
are registered trademarks of Microsoft Corporation.