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    • Extreme
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  • Extreme.DataAnalysis.Linq
    • LinqExtensions Class
    • LinqExtensions.DataFrameGrouping(TKey, R, C) Class
    • LinqExtensions.DataFrameLookup(TKey, R, C) Class
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  • LinqExtensions Class
    • Methods
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    • Aggregate Method Overloads
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  • GroupBy Method Overloads
    • GroupBy(R, C, TKey) Method (DataFrame(R, C), Func(DataFrameRow(R, C), TKey))
    • GroupBy(T, TKey) Method (Vector(T), Func(T, TKey))
    • GroupBy(R, C, TKey) Method (DataFrame(R, C), Func(DataFrameRow(R, C), TKey), IEqualityComparer(TKey))
    • GroupBy(R, C, TKey, TResult) Method (DataFrame(R, C), Func(DataFrameRow(R, C), TKey), Func(TKey, IEnumerable(DataFrameRow(R, C)), TResult))
    • GroupBy(R, C, TKey, TElement) Method (DataFrame(R, C), Func(DataFrameRow(R, C), TKey), Func(DataFrameRow(R, C), TElement))
    • GroupBy(T, TKey) Method (Vector(T), Func(T, TKey), IEqualityComparer(TKey))
    • GroupBy(T, TKey, TElement) Method (Vector(T), Func(T, TKey), Func(T, TElement))
    • GroupBy(T, TKey, TResult) Method (Vector(T), Func(T, TKey), Func(TKey, IEnumerable(T), TResult))
    • GroupBy(R, C, TKey, TResult) Method (DataFrame(R, C), Func(DataFrameRow(R, C), TKey), Func(TKey, IEnumerable(DataFrameRow(R, C)), TResult), IEqualityComparer(TKey))
    • GroupBy(R, C, TKey, TElement) Method (DataFrame(R, C), Func(DataFrameRow(R, C), TKey), Func(DataFrameRow(R, C), TElement), IEqualityComparer(TKey))
    • GroupBy(R, C, TKey, TElement, TResult) Method (DataFrame(R, C), Func(DataFrameRow(R, C), TKey), Func(DataFrameRow(R, C), TElement), Func(TKey, IEnumerable(TElement), TResult))
    • GroupBy(T, TKey, TElement) Method (Vector(T), Func(T, TKey), Func(T, TElement), IEqualityComparer(TKey))
    • GroupBy(T, TKey, TResult) Method (Vector(T), Func(T, TKey), Func(TKey, IEnumerable(T), TResult), IEqualityComparer(TKey))
    • GroupBy(T, TKey, TElement, TResult) Method (Vector(T), Func(T, TKey), Func(T, TElement), Func(TKey, IEnumerable(TElement), TResult))
    • GroupBy(R, C, TKey, TElement, TResult) Method (DataFrame(R, C), Func(DataFrameRow(R, C), TKey), Func(DataFrameRow(R, C), TElement), Func(TKey, IEnumerable(TElement), TResult), IEqualityComparer(TKey))
    • GroupBy(T, TKey, TElement, TResult) Method (Vector(T), Func(T, TKey), Func(T, TElement), Func(TKey, IEnumerable(TElement), TResult), IEqualityComparer(TKey))
  • GroupBy(T, TKey, TResult) Method (Vector(T), Func(T, TKey), Func(TKey, IEnumerable(T), TResult))

LinqExtensionsGroupByT, TKey, TResult Method (VectorT, FuncT, TKey, FuncTKey, IEnumerableT, TResult)

Extreme Optimization Numerical Libraries for .NET Professional
Groups the elements of a vector according to the specified key selector function and creates a result value from each group and its key.

Namespace:  Extreme.DataAnalysis.Linq
Assembly:  Extreme.Numerics (in Extreme.Numerics.dll) Version: 8.1.1
Syntax

C#
VB
C++
F#
Copy
public static Vector<TResult> GroupBy<T, TKey, TResult>(
	this Vector<T> vector,
	Func<T, TKey> keySelector,
	Func<TKey, IEnumerable<T>, TResult> resultSelector
)
<ExtensionAttribute>
Public Shared Function GroupBy(Of T, TKey, TResult) ( 
	vector As Vector(Of T),
	keySelector As Func(Of T, TKey),
	resultSelector As Func(Of TKey, IEnumerable(Of T), TResult)
) As Vector(Of TResult)
public:
[ExtensionAttribute]
generic<typename T, typename TKey, typename TResult>
static Vector<TResult>^ GroupBy(
	Vector<T>^ vector, 
	Func<T, TKey>^ keySelector, 
	Func<TKey, IEnumerable<T>^, TResult>^ resultSelector
)
[<ExtensionAttribute>]
static member GroupBy : 
        vector : Vector<'T> * 
        keySelector : Func<'T, 'TKey> * 
        resultSelector : Func<'TKey, IEnumerable<'T>, 'TResult> -> Vector<'TResult> 

Parameters

vector
Type: Extreme.MathematicsVectorT
A vector whose elements to group.
keySelector
Type: SystemFuncT, TKey
A function to extract the key for each element.
resultSelector
Type: SystemFuncTKey, IEnumerableT, TResult
A function that maps each group to a final result.

Type Parameters

T
The type of the elements of the vector.
TKey
The type of the keys.
TResult
The type of the final result for each group.

Return Value

Type: VectorTResult
A vector of elements of type TResult where each element is obtained by applying resultSelector to each group resulting from using keySelector to obtain the key on each element of vector.

Usage Note

In Visual Basic and C#, you can call this method as an instance method on any object of type VectorT. 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).
See Also

Reference

LinqExtensions Class
GroupBy Overload
Extreme.DataAnalysis.Linq Namespace

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