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# ComposedTabularTransformer

A transformer that composes two tabular transformers by applying them one after the other.

```
struct ComposedTabularTransformer<Inner, Outer> where Inner : TabularTransformer, Outer : TabularTransformer
```

## Overview

The result of this transformer is equivalent to invoking `outer(inner(x))` on an input `x`,

## Topics

### Creating the transformer

[`init(Inner, Outer)`](/documentation/CreateMLComponents/ComposedTabularTransformer/init(_:_:))

Creates a composed tabular transformer from two tabular transformers.

### Getting the properties

[`var inner: Inner`](/documentation/CreateMLComponents/ComposedTabularTransformer/inner)

The inner transformer.

[`var outer: Outer`](/documentation/CreateMLComponents/ComposedTabularTransformer/outer)

The outer transformer.

### Applying a transformation

[`func applied(to: DataFrame, eventHandler: EventHandler?) async throws -> DataFrame`](/documentation/CreateMLComponents/ComposedTabularTransformer/applied(to:eventHandler:))

Performs the composed transformation on a single input.

## Relationships

### Conforms To

[`Copyable`](/documentation/Swift/Copyable)

[`Sendable`](/documentation/Swift/Sendable)

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

[`Decodable`](/documentation/Swift/Decodable)

[`Escapable`](/documentation/Swift/Escapable)

[`Encodable`](/documentation/Swift/Encodable)

[`TabularTransformer`](/documentation/CreateMLComponents/TabularTransformer)

[`Equatable`](/documentation/Swift/Equatable)

[`Transformer`](/documentation/CreateMLComponents/Transformer)

[`CustomDebugStringConvertible`](/documentation/Swift/CustomDebugStringConvertible)

---

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