.. DO NOT EDIT. .. THIS FILE WAS AUTOMATICALLY GENERATED BY SPHINX-GALLERY. .. TO MAKE CHANGES, EDIT THE SOURCE PYTHON FILE: .. "auto_examples/miscellaneous/plot_set_output.py" .. LINE NUMBERS ARE GIVEN BELOW. .. only:: html .. note:: :class: sphx-glr-download-link-note Click :ref:`here ` to download the full example code or to run this example in your browser via Binder .. rst-class:: sphx-glr-example-title .. _sphx_glr_auto_examples_miscellaneous_plot_set_output.py: ================================ Introducing the `set_output` API ================================ .. currentmodule:: sklearn This example will demonstrate the `set_output` API to configure transformers to output pandas DataFrames. `set_output` can be configured per estimator by calling the `set_output` method or globally by setting `set_config(transform_output="pandas")`. For details, see `SLEP018 `__. .. GENERATED FROM PYTHON SOURCE LINES 16-17 First, we load the iris dataset as a DataFrame to demonstrate the `set_output` API. .. GENERATED FROM PYTHON SOURCE LINES 17-24 .. code-block:: default from sklearn.datasets import load_iris from sklearn.model_selection import train_test_split X, y = load_iris(as_frame=True, return_X_y=True) X_train, X_test, y_train, y_test = train_test_split(X, y, stratify=y, random_state=0) X_train.head() .. raw:: html
sepal length (cm) sepal width (cm) petal length (cm) petal width (cm)
60 5.0 2.0 3.5 1.0
1 4.9 3.0 1.4 0.2
8 4.4 2.9 1.4 0.2
93 5.0 2.3 3.3 1.0
106 4.9 2.5 4.5 1.7


.. GENERATED FROM PYTHON SOURCE LINES 25-27 To configure an estimator such as :class:`preprocessing.StandardScaler` to return DataFrames, call `set_output`. This feature requires pandas to be installed. .. GENERATED FROM PYTHON SOURCE LINES 27-36 .. code-block:: default from sklearn.preprocessing import StandardScaler scaler = StandardScaler().set_output(transform="pandas") scaler.fit(X_train) X_test_scaled = scaler.transform(X_test) X_test_scaled.head() .. raw:: html
sepal length (cm) sepal width (cm) petal length (cm) petal width (cm)
39 -0.894264 0.798301 -1.271411 -1.327605
12 -1.244466 -0.086944 -1.327407 -1.459074
48 -0.660797 1.462234 -1.271411 -1.327605
23 -0.894264 0.576989 -1.159419 -0.933197
81 -0.427329 -1.414810 -0.039497 -0.275851


.. GENERATED FROM PYTHON SOURCE LINES 37-38 `set_output` can be called after `fit` to configure `transform` after the fact. .. GENERATED FROM PYTHON SOURCE LINES 38-48 .. code-block:: default scaler2 = StandardScaler() scaler2.fit(X_train) X_test_np = scaler2.transform(X_test) print(f"Default output type: {type(X_test_np).__name__}") scaler2.set_output(transform="pandas") X_test_df = scaler2.transform(X_test) print(f"Configured pandas output type: {type(X_test_df).__name__}") .. rst-class:: sphx-glr-script-out .. code-block:: none Default output type: ndarray Configured pandas output type: DataFrame .. GENERATED FROM PYTHON SOURCE LINES 49-51 In a :class:`pipeline.Pipeline`, `set_output` configures all steps to output DataFrames. .. GENERATED FROM PYTHON SOURCE LINES 51-61 .. code-block:: default from sklearn.pipeline import make_pipeline from sklearn.linear_model import LogisticRegression from sklearn.feature_selection import SelectPercentile clf = make_pipeline( StandardScaler(), SelectPercentile(percentile=75), LogisticRegression() ) clf.set_output(transform="pandas") clf.fit(X_train, y_train) .. raw:: html
Pipeline(steps=[('standardscaler', StandardScaler()),
                    ('selectpercentile', SelectPercentile(percentile=75)),
                    ('logisticregression', LogisticRegression())])
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.. GENERATED FROM PYTHON SOURCE LINES 62-64 Each transformer in the pipeline is configured to return DataFrames. This means that the final logistic regression step contains the feature names of the input. .. GENERATED FROM PYTHON SOURCE LINES 64-66 .. code-block:: default clf[-1].feature_names_in_ .. rst-class:: sphx-glr-script-out .. code-block:: none array(['sepal length (cm)', 'petal length (cm)', 'petal width (cm)'], dtype=object) .. GENERATED FROM PYTHON SOURCE LINES 67-69 Next we load the titanic dataset to demonstrate `set_output` with :class:`compose.ColumnTransformer` and heterogenous data. .. GENERATED FROM PYTHON SOURCE LINES 69-76 .. code-block:: default from sklearn.datasets import fetch_openml X, y = fetch_openml( "titanic", version=1, as_frame=True, return_X_y=True, parser="pandas" ) X_train, X_test, y_train, y_test = train_test_split(X, y, stratify=y) .. GENERATED FROM PYTHON SOURCE LINES 77-79 The `set_output` API can be configured globally by using :func:`set_config` and setting `transform_output` to `"pandas"`. .. GENERATED FROM PYTHON SOURCE LINES 79-105 .. code-block:: default from sklearn.compose import ColumnTransformer from sklearn.preprocessing import OneHotEncoder, StandardScaler from sklearn.impute import SimpleImputer from sklearn import set_config set_config(transform_output="pandas") num_pipe = make_pipeline(SimpleImputer(), StandardScaler()) num_cols = ["age", "fare"] ct = ColumnTransformer( ( ("numerical", num_pipe, num_cols), ( "categorical", OneHotEncoder( sparse_output=False, drop="if_binary", handle_unknown="ignore" ), ["embarked", "sex", "pclass"], ), ), verbose_feature_names_out=False, ) clf = make_pipeline(ct, SelectPercentile(percentile=50), LogisticRegression()) clf.fit(X_train, y_train) clf.score(X_test, y_test) .. rst-class:: sphx-glr-script-out .. code-block:: none 0.7621951219512195 .. GENERATED FROM PYTHON SOURCE LINES 106-108 With the global configuration, all transformers output DataFrames. This allows us to easily plot the logistic regression coefficients with the corresponding feature names. .. GENERATED FROM PYTHON SOURCE LINES 108-114 .. code-block:: default import pandas as pd log_reg = clf[-1] coef = pd.Series(log_reg.coef_.ravel(), index=log_reg.feature_names_in_) _ = coef.sort_values().plot.barh() .. image-sg:: /auto_examples/miscellaneous/images/sphx_glr_plot_set_output_001.png :alt: plot set output :srcset: /auto_examples/miscellaneous/images/sphx_glr_plot_set_output_001.png :class: sphx-glr-single-img .. GENERATED FROM PYTHON SOURCE LINES 115-117 This resets `transform_output` to its default value to avoid impacting other examples when generating the scikit-learn documentation .. GENERATED FROM PYTHON SOURCE LINES 117-119 .. code-block:: default set_config(transform_output="default") .. GENERATED FROM PYTHON SOURCE LINES 120-124 When configuring the output type with :func:`config_context` the configuration at the time when `transform` or `fit_transform` are called is what counts. Setting these only when you construct or fit the transformer has no effect. .. GENERATED FROM PYTHON SOURCE LINES 124-129 .. code-block:: default from sklearn import config_context scaler = StandardScaler() scaler.fit(X_train[num_cols]) .. raw:: html
StandardScaler()
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.. GENERATED FROM PYTHON SOURCE LINES 130-135 .. code-block:: default with config_context(transform_output="pandas"): # the output of transform will be a Pandas DataFrame X_test_scaled = scaler.transform(X_test[num_cols]) X_test_scaled.head() .. raw:: html
age fare
334 -0.133660 -0.438059
885 -0.894273 -0.506893
478 -2.000619 0.182778
671 -0.548540 -0.461032
817 -0.548540 -0.487001


.. GENERATED FROM PYTHON SOURCE LINES 136-137 outside of the context manager, the output will be a NumPy array .. GENERATED FROM PYTHON SOURCE LINES 137-139 .. code-block:: default X_test_scaled = scaler.transform(X_test[num_cols]) X_test_scaled[:5] .. rst-class:: sphx-glr-script-out .. code-block:: none array([[-0.13366001, -0.4380594 ], [-0.89427284, -0.50689261], [-2.00061876, 0.18277786], [-0.54853974, -0.46103177], [-0.54853974, -0.48700054]]) .. rst-class:: sphx-glr-timing **Total running time of the script:** ( 0 minutes 0.126 seconds) .. _sphx_glr_download_auto_examples_miscellaneous_plot_set_output.py: .. only:: html .. container:: sphx-glr-footer sphx-glr-footer-example .. container:: binder-badge .. image:: images/binder_badge_logo.svg :target: https://mybinder.org/v2/gh/scikit-learn/scikit-learn/1.2.X?urlpath=lab/tree/notebooks/auto_examples/miscellaneous/plot_set_output.ipynb :alt: Launch binder :width: 150 px .. container:: sphx-glr-download sphx-glr-download-python :download:`Download Python source code: plot_set_output.py ` .. container:: sphx-glr-download sphx-glr-download-jupyter :download:`Download Jupyter notebook: plot_set_output.ipynb ` .. only:: html .. rst-class:: sphx-glr-signature `Gallery generated by Sphinx-Gallery `_