# Write a machine-learning data file

Publish / file

A variant of [Write another file format](https://meridian.online/operations/write-another-file-format).

Write a table to a format machine-learning libraries read, such as ARFF, TFRecord or a NumPy array.

Page: <https://meridian.online/operations/write-another-file-format/write-a-machine-learning-data-file>

## Status

Not built yet.

arcform does not do this yet. [Its place on the roadmap](https://meridian.online/roadmap#write-another-file-format)

## What other tools call it

Meridian's classification; an independent blind rating agreed on 95.7% of 324 rows (variant, version 3).

- KNIME Analytics Platform: [`ARFF Writer`](https://api.hub.knime.com/nodes/*5NlTwuAfjZ8w7LXH?details=full) (read 2026-09-27)
- Pentaho Data Integration: [`ARFF output`](https://docs.pentaho.com/pdia-data-integration/9.3-data-integration/pdi-transformation-steps-reference-overview) (read 2026-09-27)
- RapidMiner Studio: [`Write ARFF`](https://docs.rapidminer.com/latest/studio/operators/data_access/files/write/write_arff.html) (read 2026-09-27)
- Talend: [`tFileOutputARFF`](https://help.qlik.com/talend/en-US/components/8.0/arff/arff-component) (read 2026-09-27)
- VisiData: [`npy (saver)`](https://github.com/saulpw/visidata/blob/7609212ec2febafa9caba7183cbebfaf49627909/visidata/loaders/npy.py#L95) (read 2026-09-23)
- Yggdrasil Decision Forests: [`convert_dataset`](https://github.com/google/yggdrasil-decision-forests/blob/0a54b57c95ff0cf42ecf0310ace0513a4f32cb65/yggdrasil_decision_forests/cli/convert_dataset.cc) (read 2026-09-27)
- Yggdrasil Decision Forests: [`ydf.util.write_tf_record`](https://github.com/google/yggdrasil-decision-forests/blob/0a54b57c95ff0cf42ecf0310ace0513a4f32cb65/yggdrasil_decision_forests/port/python/ydf/util/tf_example.py) (read 2026-09-27)