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Core Types

DataFrame

DataType

DataTypeExpr

Expr

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Series

Expr Sub-namespaces

Expr.Array

Expr.Bin

Expr.Cat

Expr.Dt

Expr.Ext

Expr.List

Expr.Meta

Expr.Name

Expr.Str

Expr.Struct

Series Sub-namespaces

Series.Array

Series.Bin

Series.Cat

Series.Dt

Series.Ext

Series.List

Series.Str

Series.Struct

DataTypeExpr Sub-namespaces

DataTypeExpr.Array

DataTypeExpr.List

DataTypeExpr.Struct

DSL & Static Entrypoints

Polars

Polars.Selectors

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Delta

DeltaMergeBuilder

UnityCatalog

Auxiliary Types

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BaseExtension

Categories

ChainedWhen

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Field

FrozenCategories

GroupByBuilder

IntOrExpr

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LazyGroupBy

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Then

When

Enums

On this page

When

Namespace: Polars.CSharp

Instance Methods

Then

csharp

public Then Then(IntoExprColumn statement)

Parameters

Name	Type	Description
`statement`	`IntoExprColumn`	-

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