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# attributedStringForNotANumber

The attributed string the receiver uses to display “not a number” values.

```
@NSCopying var attributedStringForNotANumber: NSAttributedString { get set }
```

## Discussion

By default “not a number” values are displayed as the string “NaN”.

### Special Considerations

This method is for use with formatters using `NSNumberFormatterBehavior10_0` behavior.

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