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# MLParameterDescription

A description of a model parameter that includes a default value and a constraint, if applicable.

```
class MLParameterDescription
```

## Topics

### Describing the model parameter

[`defaultValue`](/documentation/CoreML/MLParameterDescription/defaultValue)

The default value for the parameter.

[`key`](/documentation/CoreML/MLParameterDescription/key)

The key for this parameter description value.

### Constraining numeric values

[`numericConstraint`](/documentation/CoreML/MLParameterDescription/numericConstraint)

The constraints of this paramter description value, if and only if the value is numerical.

[`MLNumericConstraint`](/documentation/CoreML/MLNumericConstraint)

The value limitations of a number.


---

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