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# set(_:forKey:)

Sets the value of the specified key to a floating-point number.

```
func set(_ value: Float, forKey defaultName: String)
```

## Parameters

`value`

The floating-point value to store in the defaults database.

`defaultName`

The key that contains the setting’s name.

## Discussion

This method places the floating-point value in an [`NSNumber`](/documentation/Foundation/NSNumber) type before writing the
key and value to the defaults database. After you call this method, the system generates
a [`didChangeNotification`](/documentation/Foundation/UserDefaults/didChangeNotification) for registered observers.

---

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