---
title: validationData
framework: createml
role: symbol
role_heading: Instance Property
path: createml/mldecisiontreeregressor/modelparameters-swift.struct/validationdata-swift.property
---

# validationData

Validation data represented as a MLDataTable.

## Declaration

```swift
var validationData: MLDataTable? { get set }
```

## Discussion

Discussion note: Setting this to nil means that the training data will be automatically split for validation. Setting it to an empty table means to not use a validation set.

## See Also

### Accessing parameters

- [maxDepth](createml/mldecisiontreeregressor/modelparameters-swift.struct/maxdepth.md)
- [minChildWeight](createml/mldecisiontreeregressor/modelparameters-swift.struct/minchildweight.md)
- [minLossReduction](createml/mldecisiontreeregressor/modelparameters-swift.struct/minlossreduction.md)
- [randomSeed](createml/mldecisiontreeregressor/modelparameters-swift.struct/randomseed.md)
- [validation](createml/mldecisiontreeregressor/modelparameters-swift.struct/validation.md)