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OpenML

Collaborative Machine Learning in Python

Welcome to the documentation of the OpenML Python API, a connector to the collaborative machine learning platform OpenML.org. The OpenML Python package allows to use datasets and tasks from OpenML together with scikit-learn and share the results online.

Example

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import openml
from sklearn import impute, tree, pipeline

# Define a scikit-learn classifier or pipeline
clf = pipeline.Pipeline(
    steps=[
        ('imputer', impute.SimpleImputer()),
        ('estimator', tree.DecisionTreeClassifier())
    ]
)
# Download the OpenML task for the pendigits dataset with 10-fold
# cross-validation.
task = openml.tasks.get_task(32)
# Run the scikit-learn model on the task.
run = openml.runs.run_model_on_task(clf, task)
# Publish the experiment on OpenML (optional, requires an API key.
# You can get your own API key by signing up to OpenML.org)
run.publish()
print(f'View the run online: {run.openml_url}')

Find more examples in the sidebar on the left.

How to get OpenML for python

You can install the OpenML package via pip (we recommend using a virtual environment):

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python -m pip install openml

For more advanced installation information, please see the "Introduction" example.

Further information

Contributing

Contribution to the OpenML package is highly appreciated. Please see the "Contributing" page for more information.

Citing OpenML-Python

If you use OpenML-Python in a scientific publication, we would appreciate a reference to our JMLR-MLOSS paper "OpenML-Python: an extensible Python API for OpenML":

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@article{JMLR:v22:19-920,
    author  = {Matthias Feurer and Jan N. van Rijn and Arlind Kadra and Pieter Gijsbers and Neeratyoy Mallik and Sahithya Ravi and Andreas Müller and Joaquin Vanschoren and Frank Hutter},
    title   = {OpenML-Python: an extensible Python API for OpenML},
    journal = {Journal of Machine Learning Research},
    year    = {2021},
    volume  = {22},
    number  = {100},
    pages   = {1--5},
    url     = {http://jmlr.org/papers/v22/19-920.html}
}

Feurer, Matthias, et al. "OpenML-Python: an extensible Python API for OpenML." Journal of Machine Learning Research 22.100 (2021):1−5.