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# ConcatenationError

Errors thrown when concatenating numeric values.

```
enum ConcatenationError
```

## Topics

### Analyzing the error

[`case mismatchedShapes`](/documentation/CreateMLComponents/ConcatenationError/mismatchedShapes)

Shaped arrays across columns have mismatched shapes and can’t be concatenated.

[`case nonUniformShapes(columnName: String)`](/documentation/CreateMLComponents/ConcatenationError/nonUniformShapes(columnName:))

A column contains arrays or shaped arrays with non-uniform shapes.

### Getting the debug description

[`var debugDescription: String`](/documentation/CreateMLComponents/ConcatenationError/debugDescription)

A text representation of the error.

### Default Implementations

[CustomDebugStringConvertible Implementations](/documentation/CreateMLComponents/ConcatenationError/CustomDebugStringConvertible-Implementations)

## Relationships

### Conforms To

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

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

[`LocalizedError`](/documentation/Foundation/LocalizedError)

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

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

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

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

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

---

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