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.. include:: _contributors.rst

.. currentmodule:: sklearn

.. _changes_0_24_2:

Version 0.24.2
==============

**April 2021**

Changelog
---------

:mod:`sklearn.compose`
......................

- |Fix| `compose.ColumnTransformer.get_feature_names` does not call
  `get_feature_names` on transformers with an empty column selection.
  :pr:`19579` by `Thomas Fan`_.

:mod:`sklearn.cross_decomposition`
..................................

- |Fix| Fixed a regression in :class:`cross_decomposition.CCA`. :pr:`19646`
  by `Thomas Fan`_.

- |Fix| :class:`cross_decomposition.PLSRegression` raises warning for
  constant y residuals instead of a `StopIteration` error. :pr:`19922`
  by `Thomas Fan`_.

:mod:`sklearn.decomposition`
............................

- |Fix| Fixed a bug in :class:`decomposition.KernelPCA`'s
  ``inverse_transform``.  :pr:`19732` by :user:`Kei Ishikawa <kstoneriv3>`.

:mod:`sklearn.ensemble`
.......................

- |Fix| Fixed a bug in :class:`ensemble.HistGradientBoostingRegressor` `fit`
  with `sample_weight` parameter and `least_absolute_deviation` loss function.
  :pr:`19407` by :user:`Vadim Ushtanit <vadim-ushtanit>`.

:mod:`feature_extraction`
.........................

- |Fix| Fixed a bug to support multiple strings for a category when
  `sparse=False` in :class:`feature_extraction.DictVectorizer`.
  :pr:`19982` by :user:`Guillaume Lemaitre <glemaitre>`.

:mod:`sklearn.gaussian_process`
...............................

- |Fix| Avoid explicitly forming inverse covariance matrix in
  :class:`gaussian_process.GaussianProcessRegressor` when set to output
  standard deviation. With certain covariance matrices this inverse is unstable
  to compute explicitly. Calling Cholesky solver mitigates this issue in
  computation.
  :pr:`19939` by :user:`Ian Halvic <iwhalvic>`.

- |Fix| Avoid division by zero when scaling constant target in
  :class:`gaussian_process.GaussianProcessRegressor`. It was due to a std. dev.
  equal to 0. Now, such case is detected and the std. dev. is affected to 1
  avoiding a division by zero and thus the presence of NaN values in the
  normalized target.
  :pr:`19703` by :user:`sobkevich`, :user:`Boris Villazón-Terrazas <boricles>`
  and :user:`Alexandr Fonari <afonari>`.

:mod:`sklearn.linear_model`
...........................

- |Fix|: Fixed a bug in :class:`linear_model.LogisticRegression`: the
  sample_weight object is not modified anymore. :pr:`19182` by
  :user:`Yosuke KOBAYASHI <m7142yosuke>`.

:mod:`sklearn.metrics`
......................

- |Fix| :func:`metrics.top_k_accuracy_score` now supports multiclass
  problems where only two classes appear in `y_true` and all the classes
  are specified in `labels`.
  :pr:`19721` by :user:`Joris Clement <flyingdutchman23>`.

:mod:`sklearn.model_selection`
..............................

- |Fix| :class:`model_selection.RandomizedSearchCV` and
  :class:`model_selection.GridSearchCV` now correctly shows the score for
  single metrics and verbose > 2. :pr:`19659` by `Thomas Fan`_.

- |Fix| Some values in the `cv_results_` attribute of
  :class:`model_selection.HalvingRandomSearchCV` and
  :class:`model_selection.HalvingGridSearchCV` were not properly converted to
  numpy arrays. :pr:`19211` by `Nicolas Hug`_.

- |Fix| The `fit` method of the successive halving parameter search
  (:class:`model_selection.HalvingGridSearchCV`, and
  :class:`model_selection.HalvingRandomSearchCV`) now correctly handles the
  `groups` parameter. :pr:`19847` by :user:`Xiaoyu Chai <xiaoyuchai>`.

:mod:`sklearn.multioutput`
..........................

- |Fix| :class:`multioutput.MultiOutputRegressor` now works with estimators
  that dynamically define `predict` during fitting, such as
  :class:`ensemble.StackingRegressor`. :pr:`19308` by `Thomas Fan`_.

:mod:`sklearn.preprocessing`
............................

- |Fix| Validate the constructor parameter `handle_unknown` in
  :class:`preprocessing.OrdinalEncoder` to only allow for `'error'` and
  `'use_encoded_value'` strategies.
  :pr:`19234` by `Guillaume Lemaitre <glemaitre>`.

- |Fix| Fix encoder categories having dtype='S'
  :class:`preprocessing.OneHotEncoder` and
  :class:`preprocessing.OrdinalEncoder`.
  :pr:`19727` by :user:`Andrew Delong <andrewdelong>`.

- |Fix| :meth:`preprocessing.OrdinalEncoder.transfrom` correctly handles
  unknown values for string dtypes. :pr:`19888` by `Thomas Fan`_.

- |Fix| :meth:`preprocessing.OneHotEncoder.fit` no longer alters the `drop`
  parameter. :pr:`19924` by `Thomas Fan`_.

:mod:`sklearn.semi_supervised`
..............................

- |Fix| Avoid NaN during label propagation in
  :class:`~sklearn.semi_supervised.LabelPropagation`.
  :pr:`19271` by :user:`Zhaowei Wang <ThuWangzw>`.

:mod:`sklearn.tree`
...................

- |Fix| Fix a bug in `fit` of :class:`tree.BaseDecisionTree` that caused
  segmentation faults under certain conditions. `fit` now deep copies the
  `Criterion` object to prevent shared concurrent accesses.
  :pr:`19580` by :user:`Samuel Brice <samdbrice>` and
  :user:`Alex Adamson <aadamson>` and
  :user:`Wil Yegelwel <wyegelwel>`.

:mod:`sklearn.utils`
....................

- |Fix| Better contains the CSS provided by :func:`utils.estimator_html_repr`
  by giving CSS ids to the html representation. :pr:`19417` by `Thomas Fan`_.

.. _changes_0_24_1:

Version 0.24.1
==============

**January 2021**

Packaging
---------

The 0.24.0 scikit-learn wheels were not working with MacOS <1.15 due to
`libomp`. The version of `libomp` used to build the wheels was too recent for
older macOS versions. This issue has been fixed for 0.24.1 scikit-learn wheels.
Scikit-learn wheels published on PyPI.org now officially support macOS 10.13
and later.

Changelog
---------

:mod:`sklearn.metrics`
......................

- |Fix| Fix numerical stability bug that could happen in
  :func:`metrics.adjusted_mutual_info_score` and
  :func:`metrics.mutual_info_score` with NumPy 1.20+.
  :pr:`19179` by `Thomas Fan`_.

:mod:`sklearn.semi_supervised`
..............................

- |Fix| :class:`semi_supervised.SelfTrainingClassifier` is now accepting
  meta-estimator (e.g. :class:`ensemble.StackingClassifier`). The validation
  of this estimator is done on the fitted estimator, once we know the existence
  of the method `predict_proba`.
  :pr:`19126` by :user:`Guillaume Lemaitre <glemaitre>`.

.. _changes_0_24:

Version 0.24.0
==============

**December 2020**

For a short description of the main highlights of the release, please
refer to
:ref:`sphx_glr_auto_examples_release_highlights_plot_release_highlights_0_24_0.py`.

.. include:: changelog_legend.inc

Put the changes in their relevant module.

Changed models
--------------

The following estimators and functions, when fit with the same data and
parameters, may produce different models from the previous version. This often
occurs due to changes in the modelling logic (bug fixes or enhancements), or in
random sampling procedures.

- |Fix| :class:`decomposition.KernelPCA` behaviour is now more consistent
  between 32-bits and 64-bits data when the kernel has small positive
  eigenvalues.

- |Fix| :class:`decomposition.TruncatedSVD` becomes deterministic by exposing
  a `random_state` parameter.

- |Fix| :class:`linear_model.Perceptron` when `penalty='elasticnet'`.

- |Fix| Change in the random sampling procedures for the center initialization
  of :class:`cluster.KMeans`.

Details are listed in the changelog below.

(While we are trying to better inform users by providing this information, we
cannot assure that this list is complete.)

Changelog
---------

:mod:`sklearn.base`
...................

- |Fix| :meth:`base.BaseEstimator.get_params` now will raise an
  `AttributeError` if a parameter cannot be retrieved as
  an instance attribute. Previously it would return `None`.
  :pr:`17448` by :user:`Juan Carlos Alfaro Jiménez <alfaro96>`.

:mod:`sklearn.calibration`
..........................

- |Efficiency| :class:`calibration.CalibratedClassifierCV.fit` now supports
  parallelization via `joblib.Parallel` using argument `n_jobs`.
  :pr:`17107` by :user:`Julien Jerphanion <jjerphan>`.

- |Enhancement| Allow :class:`calibration.CalibratedClassifierCV` use with
  prefit :class:`pipeline.Pipeline` where data is not `X` is not array-like,
  sparse matrix or dataframe at the start. :pr:`17546` by
  :user:`Lucy Liu <lucyleeow>`.

- |Enhancement| Add `ensemble` parameter to
  :class:`calibration.CalibratedClassifierCV`, which enables implementation
  of calibration via an ensemble of calibrators (current method) or
  just one calibrator using all the data (similar to the built-in feature of
  :mod:`sklearn.svm` estimators with the `probabilities=True` parameter).
  :pr:`17856` by :user:`Lucy Liu <lucyleeow>` and
  :user:`Andrea Esuli <aesuli>`.

:mod:`sklearn.cluster`
......................

- |Enhancement| :class:`cluster.AgglomerativeClustering` has a new parameter
  `compute_distances`. When set to `True`, distances between clusters are
  computed and stored in the `distances_` attribute even when the parameter
  `distance_threshold` is not used. This new parameter is useful to produce
  dendrogram visualizations, but introduces a computational and memory
  overhead. :pr:`17984` by :user:`Michael Riedmann <mriedmann>`,
  :user:`Emilie Delattre <EmilieDel>`, and
  :user:`Francesco Casalegno <FrancescoCasalegno>`.

- |Enhancement| :class:`cluster.SpectralClustering` and
  :func:`cluster.spectral_clustering` have a new keyword argument `verbose`.
  When set to `True`, additional messages will be displayed which can aid with
  debugging. :pr:`18052` by :user:`Sean O. Stalley <sstalley>`.

- |Enhancement| Added :func:`cluster.kmeans_plusplus` as public function.
  Initialization by KMeans++ can now be called separately to generate
  initial cluster centroids. :pr:`17937` by :user:`g-walsh`

- |API| :class:`cluster.MiniBatchKMeans` attributes, `counts_` and
  `init_size_`, are deprecated and will be removed in 1.1 (renaming of 0.26).
  :pr:`17864` by :user:`Jérémie du Boisberranger <jeremiedbb>`.

:mod:`sklearn.compose`
......................

- |Fix| :class:`compose.ColumnTransformer` will skip transformers the
  column selector is a list of bools that are False. :pr:`17616` by
  `Thomas Fan`_.

- |Fix| :class:`compose.ColumnTransformer` now displays the remainder in the
  diagram display. :pr:`18167` by `Thomas Fan`_.

- |Fix| :class:`compose.ColumnTransformer` enforces strict count and order
  of column names between `fit` and `transform` by raising an error instead
  of a warning, following the deprecation cycle.
  :pr:`18256` by :user:`Madhura Jayratne <madhuracj>`.

:mod:`sklearn.covariance`
.........................

- |API| Deprecates `cv_alphas_` in favor of `cv_results_['alphas']` and
  `grid_scores_` in favor of split scores in `cv_results_` in
  :class:`covariance.GraphicalLassoCV`. `cv_alphas_` and `grid_scores_` will be
  removed in version 1.1 (renaming of 0.26).
  :pr:`16392` by `Thomas Fan`_.

:mod:`sklearn.cross_decomposition`
..................................

- |Fix| Fixed a bug in :class:`cross_decomposition.PLSSVD` which would
  sometimes return components in the reversed order of importance.
  :pr:`17095` by `Nicolas Hug`_.

- |Fix| Fixed a bug in :class:`cross_decomposition.PLSSVD`,
  :class:`cross_decomposition.CCA`, and
  :class:`cross_decomposition.PLSCanonical`, which would lead to incorrect
  predictions for `est.transform(Y)` when the training data is single-target.
  :pr:`17095` by `Nicolas Hug`_.

- |Fix| Increases the stability of :class:`cross_decomposition.CCA` :pr:`18746`
  by `Thomas Fan`_.

- |API| For :class:`cross_decomposition.NMF`,
  the `init` value, when 'init=None' and
  n_components <= min(n_samples, n_features) will be changed from
  `'nndsvd'` to `'nndsvda'` in 1.1 (renaming of 0.26).
  :pr:`18525` by :user:`Chiara Marmo <cmarmo>`.

- |API| The bounds of the `n_components` parameter is now restricted:

  - into `[1, min(n_samples, n_features, n_targets)]`, for
    :class:`cross_decomposition.PLSSVD`, :class:`cross_decomposition.CCA`,
    and :class:`cross_decomposition.PLSCanonical`.
  - into `[1, n_features]` or :class:`cross_decomposition.PLSRegression`.

  An error will be raised in 1.1 (renaming of 0.26).
  :pr:`17095` by `Nicolas Hug`_.

- |API| For :class:`cross_decomposition.PLSSVD`,
  :class:`cross_decomposition.CCA`, and
  :class:`cross_decomposition.PLSCanonical`, the `x_scores_` and `y_scores_`
  attributes were deprecated and will be removed in 1.1 (renaming of 0.26).
  They can be retrieved by calling `transform` on the training data.
  The `norm_y_weights` attribute will also be removed.
  :pr:`17095` by `Nicolas Hug`_.

- |API| For :class:`cross_decomposition.PLSRegression`,
  :class:`cross_decomposition.PLSCanonical`,
  :class:`cross_decomposition.CCA`, and
  :class:`cross_decomposition.PLSSVD`, the `x_mean_`, `y_mean_`, `x_std_`, and
  `y_std_` attributes were deprecated and will be removed in 1.1
  (renaming of 0.26).
  :pr:`18768` by :user:`Maren Westermann <marenwestermann>`.

- |Fix| :class:`decomposition.TruncatedSVD` becomes deterministic by using the
  `random_state`. It controls the weights' initialization of the underlying
  ARPACK solver.
  :pr:` #18302` by :user:`Gaurav Desai <gauravkdesai>` and
  :user:`Ivan Panico <FollowKenny>`.

:mod:`sklearn.datasets`
.......................

- |Feature| :func:`datasets.fetch_openml` now validates md5 checksum of arff
  files downloaded or cached to ensure data integrity.
  :pr:`14800` by :user:`Shashank Singh <shashanksingh28>` and `Joel Nothman`_.

- |Enhancement| :func:`datasets.fetch_openml` now allows argument `as_frame`
  to be 'auto', which tries to convert returned data to pandas DataFrame
  unless data is sparse.
  :pr:`17396` by :user:`Jiaxiang <fujiaxiang>`.

- |Enhancement| :func:`datasets.fetch_covtype` now supports the optional
  argument `as_frame`; when it is set to True, the returned Bunch object's
  `data` and `frame` members are pandas DataFrames, and the `target` member is
  a pandas Series.
  :pr:`17491` by :user:`Alex Liang <tianchuliang>`.

- |Enhancement| :func:`datasets.fetch_kddcup99` now supports the optional
  argument `as_frame`; when it is set to True, the returned Bunch object's
  `data` and `frame` members are pandas DataFrames, and the `target` member is
  a pandas Series.
  :pr:`18280` by :user:`Alex Liang <tianchuliang>` and
  `Guillaume Lemaitre`_.

- |Enhancement| :func:`datasets.fetch_20newsgroups_vectorized` now supports
  loading as a pandas ``DataFrame`` by setting ``as_frame=True``.
  :pr:`17499` by :user:`Brigitta Sipőcz <bsipocz>` and
  `Guillaume Lemaitre`_.

- |API| The default value of `as_frame` in :func:`datasets.fetch_openml` is
  changed from False to 'auto'.
  :pr:`17610` by :user:`Jiaxiang <fujiaxiang>`.

:mod:`sklearn.decomposition`
............................

- |Enhancement| :func:`decomposition.FactorAnalysis` now supports the optional
  argument `rotation`, which can take the value `None`, `'varimax'` or
  `'quartimax'`. :pr:`11064` by :user:`Jona Sassenhagen <jona-sassenhagen>`.

- |Enhancement| :class:`decomposition.NMF` now supports the optional parameter
  `regularization`, which can take the values `None`, 'components',
  'transformation' or 'both', in accordance with
  :func:`decomposition.NMF.non_negative_factorization`.
  :pr:`17414` by :user:`Bharat Raghunathan <Bharat123rox>`.

- |Fix| :class:`decomposition.KernelPCA` behaviour is now more consistent
  between 32-bits and 64-bits data input when the kernel has small positive
  eigenvalues. Small positive eigenvalues were not correctly discarded for
  32-bits data.
  :pr:`18149` by :user:`Sylvain Marié <smarie>`.

- |Fix| Fix :class:`decomposition.SparseCoder` such that it follows
  scikit-learn API and support cloning. The attribute `components_` is
  deprecated in 0.24 and will be removed in 1.1 (renaming of 0.26).
  This attribute was redundant with the `dictionary` attribute and constructor
  parameter.
  :pr:`17679` by :user:`Xavier Dupré <sdpython>`.

- |Fix| :meth:`TruncatedSVD.fit_transform` consistently returns the same
  as :meth:`TruncatedSVD.fit` followed by :meth:`TruncatedSVD.transform`.
  :pr:`18528` by :user:`Albert Villanova del Moral <albertvillanova>` and
  :user:`Ruifeng Zheng <zhengruifeng>`.

:mod:`sklearn.discriminant_analysis`
....................................

- |Enhancement| :class:`discriminant_analysis.LinearDiscriminantAnalysis` can
  now use custom covariance estimate by setting the `covariance_estimator`
  parameter. :pr:`14446` by :user:`Hugo Richard <hugorichard>`.

:mod:`sklearn.ensemble`
.......................

- |MajorFeature| :class:`ensemble.HistGradientBoostingRegressor` and
  :class:`ensemble.HistGradientBoostingClassifier` now have native
  support for categorical features with the `categorical_features`
  parameter. :pr:`18394` by `Nicolas Hug`_ and `Thomas Fan`_.

- |Feature| :class:`ensemble.HistGradientBoostingRegressor` and
  :class:`ensemble.HistGradientBoostingClassifier` now support the
  method `staged_predict`, which allows monitoring of each stage.
  :pr:`16985` by :user:`Hao Chun Chang <haochunchang>`.

- |Efficiency| break cyclic references in the tree nodes used internally in
  :class:`ensemble.HistGradientBoostingRegressor` and
  :class:`ensemble.HistGradientBoostingClassifier` to allow for the timely
  garbage collection of large intermediate datastructures and to improve memory
  usage in `fit`. :pr:`18334` by `Olivier Grisel`_ `Nicolas Hug`_, `Thomas
  Fan`_ and `Andreas Müller`_.

- |Efficiency| Histogram initialization is now done in parallel in
  :class:`ensemble.HistGradientBoostingRegressor` and
  :class:`ensemble.HistGradientBoostingClassifier` which results in speed
  improvement for problems that build a lot of nodes on multicore machines.
  :pr:`18341` by `Olivier Grisel`_, `Nicolas Hug`_, `Thomas Fan`_, and
  :user:`Egor Smirnov <SmirnovEgorRu>`.

- |Fix| Fixed a bug in
  :class:`ensemble.HistGradientBoostingRegressor` and
  :class:`ensemble.HistGradientBoostingClassifier` which can now accept data
  with `uint8` dtype in `predict`. :pr:`18410` by `Nicolas Hug`_.

- |API| The parameter ``n_classes_`` is now deprecated in
  :class:`ensemble.GradientBoostingRegressor` and returns `1`.
  :pr:`17702` by :user:`Simona Maggio <simonamaggio>`.

- |API| Mean absolute error ('mae') is now deprecated for the parameter
  ``criterion`` in :class:`ensemble.GradientBoostingRegressor` and
  :class:`ensemble.GradientBoostingClassifier`.
  :pr:`18326` by :user:`Madhura Jayaratne <madhuracj>`.

:mod:`sklearn.exceptions`
.........................

- |API| :class:`exceptions.ChangedBehaviorWarning` and
  :class:`exceptions.NonBLASDotWarning` are deprecated and will be removed in
  1.1 (renaming of 0.26).
  :pr:`17804` by `Adrin Jalali`_.

:mod:`sklearn.feature_extraction`
.................................

- |Enhancement| :class:`feature_extraction.DictVectorizer` accepts multiple
  values for one categorical feature. :pr:`17367` by :user:`Peng Yu <yupbank>`
  and :user:`Chiara Marmo <cmarmo>`.

- |Fix| :class:`feature_extraction.CountVectorizer` raises an issue if a
  custom token pattern which capture more than one group is provided.
  :pr:`15427` by :user:`Gangesh Gudmalwar <ggangesh>` and
  :user:`Erin R Hoffman <hoffm386>`.

:mod:`sklearn.feature_selection`
................................

- |Feature| Added :class:`feature_selection.SequentialFeatureSelector`
  which implements forward and backward sequential feature selection.
  :pr:`6545` by `Sebastian Raschka`_ and :pr:`17159` by `Nicolas Hug`_.

- |Feature| A new parameter `importance_getter` was added to
  :class:`feature_selection.RFE`, :class:`feature_selection.RFECV` and
  :class:`feature_selection.SelectFromModel`, allowing the user to specify an
  attribute name/path or a `callable` for extracting feature importance from
  the estimator.  :pr:`15361` by :user:`Venkatachalam N <venkyyuvy>`.

- |Efficiency| Reduce memory footprint in
  :func:`feature_selection.mutual_info_classif`
  and :func:`feature_selection.mutual_info_regression` by calling
  :class:`neighbors.KDTree` for counting nearest neighbors. :pr:`17878` by
  :user:`Noel Rogers <noelano>`.

- |Enhancement| :class:`feature_selection.RFE` supports the option for the
  number of `n_features_to_select` to be given as a float representing the
  percentage of features to select.
  :pr:`17090` by :user:`Lisa Schwetlick <lschwetlick>` and
  :user:`Marija Vlajic Wheeler <marijavlajic>`.

:mod:`sklearn.gaussian_process`
...............................

- |Enhancement| A new method
  :meth:`gaussian_process.Kernel._check_bounds_params` is called after
  fitting a Gaussian Process and raises a ``ConvergenceWarning`` if the bounds
  of the hyperparameters are too tight.
  :issue:`12638` by :user:`Sylvain Lannuzel <SylvainLan>`.

:mod:`sklearn.impute`
.....................

- |Feature| :class:`impute.SimpleImputer` now supports a list of strings
  when ``strategy='most_frequent'`` or ``strategy='constant'``.
  :pr:`17526` by :user:`Ayako YAGI <yagi-3>` and
  :user:`Juan Carlos Alfaro Jiménez <alfaro96>`.

- |Feature| Added method :meth:`impute.SimpleImputer.inverse_transform` to
  revert imputed data to original when instantiated with
  ``add_indicator=True``. :pr:`17612` by :user:`Srimukh Sripada <d3b0unce>`.

- |Fix| replace the default values in :class:`impute.IterativeImputer`
  of `min_value` and `max_value` parameters to `-np.inf` and `np.inf`,
  respectively instead of `None`. However, the behaviour of the class does not
  change since `None` was defaulting to these values already.
  :pr:`16493` by :user:`Darshan N <DarshanGowda0>`.

- |Fix| :class:`impute.IterativeImputer` will not attempt to set the
  estimator's `random_state` attribute, allowing to use it with more external classes.
  :pr:`15636` by :user:`David Cortes <david-cortes>`.

- |Efficiency| :class:`impute.SimpleImputer` is now faster with `object` dtype array.
  when `strategy='most_frequent'` in :class:`~sklearn.impute.SimpleImputer`.
  :pr:`18987` by :user:`David Katz <DavidKatz-il>`.

:mod:`sklearn.inspection`
.........................

- |Feature| :func:`inspection.partial_dependence` and
  :func:`inspection.plot_partial_dependence` now support calculating and
  plotting Individual Conditional Expectation (ICE) curves controlled by the
  ``kind`` parameter.
  :pr:`16619` by :user:`Madhura Jayratne <madhuracj>`.

- |Feature| Add `sample_weight` parameter to
  :func:`inspection.permutation_importance`. :pr:`16906` by
  :user:`Roei Kahny <RoeiKa>`.

- |API| Positional arguments are deprecated in
  :meth:`inspection.PartialDependenceDisplay.plot` and will error in 1.1
  (renaming of 0.26).
  :pr:`18293` by `Thomas Fan`_.

:mod:`sklearn.isotonic`
.......................

- |Feature| Expose fitted attributes ``X_thresholds_`` and ``y_thresholds_``
  that hold the de-duplicated interpolation thresholds of an
  :class:`isotonic.IsotonicRegression` instance for model inspection purpose.
  :pr:`16289` by :user:`Masashi Kishimoto <kishimoto-banana>` and
  :user:`Olivier Grisel <ogrisel>`.

- |Enhancement| :class:`isotonic.IsotonicRegression` now accepts 2d array with
  1 feature as input array. :pr:`17379` by :user:`Jiaxiang <fujiaxiang>`.

- |Fix| Add tolerance when determining duplicate X values to prevent
  inf values from being predicted by :class:`isotonic.IsotonicRegression`.
  :pr:`18639` by :user:`Lucy Liu <lucyleeow>`.

:mod:`sklearn.kernel_approximation`
...................................

- |Feature| Added class :class:`kernel_approximation.PolynomialCountSketch`
  which implements the Tensor Sketch algorithm for polynomial kernel feature
  map approximation.
  :pr:`13003` by :user:`Daniel López Sánchez <lopeLH>`.

- |Efficiency| :class:`kernel_approximation.Nystroem` now supports
  parallelization via `joblib.Parallel` using argument `n_jobs`.
  :pr:`18545` by :user:`Laurenz Reitsam <LaurenzReitsam>`.

:mod:`sklearn.linear_model`
...........................

- |Feature| :class:`linear_model.LinearRegression` now forces coefficients
  to be all positive when ``positive`` is set to ``True``.
  :pr:`17578` by :user:`Joseph Knox <jknox13>`,
  :user:`Nelle Varoquaux <NelleV>` and :user:`Chiara Marmo <cmarmo>`.

- |Enhancement| :class:`linear_model.RidgeCV` now supports finding an optimal
  regularization value `alpha` for each target separately by setting
  ``alpha_per_target=True``. This is only supported when using the default
  efficient leave-one-out cross-validation scheme ``cv=None``. :pr:`6624` by
  :user:`Marijn van Vliet <wmvanvliet>`.

- |Fix| Fixes bug in :class:`linear_model.TheilSenRegressor` where
  `predict` and `score` would fail when `fit_intercept=False` and there was
  one feature during fitting. :pr:`18121` by `Thomas Fan`_.

- |Fix| Fixes bug in :class:`linear_model.ARDRegression` where `predict`
  was raising an error when `normalize=True` and `return_std=True` because
  `X_offset_` and `X_scale_` were undefined.
  :pr:`18607` by :user:`fhaselbeck <fhaselbeck>`.

- |Fix| Added the missing `l1_ratio` parameter in
  :class:`linear_model.Perceptron`, to be used when `penalty='elasticnet'`.
  This changes the default from 0 to 0.15. :pr:`18622` by
  :user:`Haesun Park <rickiepark>`.

:mod:`sklearn.manifold`
.......................

- |Efficiency| Fixed :issue:`10493`. Improve Local Linear Embedding (LLE)
  that raised `MemoryError` exception when used with large inputs.
  :pr:`17997` by :user:`Bertrand Maisonneuve <bmaisonn>`.

- |Enhancement| Add `square_distances` parameter to :class:`manifold.TSNE`,
  which provides backward compatibility during deprecation of legacy squaring
  behavior. Distances will be squared by default in 1.1 (renaming of 0.26),
  and this parameter will be removed in 1.3. :pr:`17662` by
  :user:`Joshua Newton <joshuacwnewton>`.

- |Fix| :class:`manifold.MDS` now correctly sets its `_pairwise` attribute.
  :pr:`18278` by `Thomas Fan`_.

:mod:`sklearn.metrics`
......................

- |Feature| Added :func:`metrics.cluster.pair_confusion_matrix` implementing
  the confusion matrix arising from pairs of elements from two clusterings.
  :pr:`17412` by :user:`Uwe F Mayer <ufmayer>`.

- |Feature| new metric :func:`metrics.top_k_accuracy_score`. It's a
  generalization of :func:`metrics.top_k_accuracy_score`, the difference is
  that a prediction is considered correct as long as the true label is
  associated with one of the `k` highest predicted scores.
  :func:`accuracy_score` is the special case of `k = 1`.
  :pr:`16625` by :user:`Geoffrey Bolmier <gbolmier>`.

- |Feature| Added :func:`metrics.det_curve` to compute Detection Error Tradeoff
  curve classification metric.
  :pr:`10591` by :user:`Jeremy Karnowski <jkarnows>` and
  :user:`Daniel Mohns <dmohns>`.

- |Feature| Added :func:`metrics.plot_det_curve` and
  :class:`metrics.DetCurveDisplay` to ease the plot of DET curves.
  :pr:`18176` by :user:`Guillaume Lemaitre <glemaitre>`.

- |Feature| Added :func:`metrics.mean_absolute_percentage_error` metric and
  the associated scorer for regression problems. :issue:`10708` fixed with the
  PR :pr:`15007` by :user:`Ashutosh Hathidara <ashutosh1919>`. The scorer and
  some practical test cases were taken from PR :pr:`10711` by
  :user:`Mohamed Ali Jamaoui <mohamed-ali>`.

- |Feature| Added :func:`metrics.rand_score` implementing the (unadjusted)
  Rand index.
  :pr:`17412` by :user:`Uwe F Mayer <ufmayer>`.

- |Feature| :func:`metrics.plot_confusion_matrix` now supports making colorbar
  optional in the matplotlib plot by setting `colorbar=False`. :pr:`17192` by
  :user:`Avi Gupta <avigupta2612>`

- |Feature| :func:`metrics.plot_confusion_matrix` now supports making colorbar
  optional in the matplotlib plot by setting colorbar=False. :pr:`17192` by
  :user:`Avi Gupta <avigupta2612>`.

- |Enhancement| Add `sample_weight` parameter to
  :func:`metrics.median_absolute_error`. :pr:`17225` by
  :user:`Lucy Liu <lucyleeow>`.

- |Enhancement| Add `pos_label` parameter in
  :func:`metrics.plot_precision_recall_curve` in order to specify the positive
  class to be used when computing the precision and recall statistics.
  :pr:`17569` by :user:`Guillaume Lemaitre <glemaitre>`.

- |Enhancement| Add `pos_label` parameter in
  :func:`metrics.plot_roc_curve` in order to specify the positive
  class to be used when computing the roc auc statistics.
  :pr:`17651` by :user:`Clara Matos <claramatos>`.

- |Fix| Fixed a bug in
  :func:`metrics.classification_report` which was raising AttributeError
  when called with `output_dict=True` for 0-length values.
  :pr:`17777` by :user:`Shubhanshu Mishra <napsternxg>`.

- |Fix| Fixed a bug in
  :func:`metrics.classification_report` which was raising AttributeError
  when called with `output_dict=True` for 0-length values.
  :pr:`17777` by :user:`Shubhanshu Mishra <napsternxg>`.

- |Fix| Fixed a bug in
  :func:`metrics.jaccard_score` which recommended the `zero_division`
  parameter when called with no true or predicted samples.
  :pr:`17826` by :user:`Richard Decal <crypdick>` and
  :user:`Joseph Willard <josephwillard>`

- |Fix| bug in :func:`metrics.hinge_loss` where error occurs when
  ``y_true`` is missing some labels that are provided explicitly in the
  ``labels`` parameter.
  :pr:`17935` by :user:`Cary Goltermann <Ultramann>`.

- |Fix| Fix scorers that accept a pos_label parameter and compute their metrics
  from values returned by `decision_function` or `predict_proba`. Previously,
  they would return erroneous values when pos_label was not corresponding to
  `classifier.classes_[1]`. This is especially important when training
  classifiers directly with string labeled target classes.
  :pr:`18114` by :user:`Guillaume Lemaitre <glemaitre>`.

- |Fix| Fixed bug in :func:`metrics.plot_confusion_matrix` where error occurs
  when `y_true` contains labels that were not previously seen by the classifier
  while the `labels` and `display_labels` parameters are set to `None`.
  :pr:`18405` by :user:`Thomas J. Fan <thomasjpfan>` and
  :user:`Yakov Pchelintsev <kyouma>`.

:mod:`sklearn.model_selection`
..............................

- |MajorFeature| Added (experimental) parameter search estimators
  :class:`model_selection.HalvingRandomSearchCV` and
  :class:`model_selection.HalvingGridSearchCV` which implement Successive
  Halving, and can be used as a drop-in replacements for
  :class:`model_selection.RandomizedSearchCV` and
  :class:`model_selection.GridSearchCV`. :pr:`13900` by `Nicolas Hug`_, `Joel
  Nothman`_ and `Andreas Müller`_.

- |Feature| :class:`model_selection.RandomizedSearchCV` and
  :class:`model_selection.GridSearchCV` now have the method ``score_samples``
  :pr:`17478` by :user:`Teon Brooks <teonbrooks>` and
  :user:`Mohamed Maskani <maskani-moh>`.

- |Enhancement| :class:`model_selection.TimeSeriesSplit` has two new keyword
  arguments `test_size` and `gap`. `test_size` allows the out-of-sample
  time series length to be fixed for all folds. `gap` removes a fixed number of
  samples between the train and test set on each fold.
  :pr:`13204` by :user:`Kyle Kosic <kykosic>`.

- |Enhancement| :func:`model_selection.permutation_test_score` and
  :func:`model_selection.validation_curve` now accept fit_params
  to pass additional estimator parameters.
  :pr:`18527` by :user:`Gaurav Dhingra <gxyd>`,
  :user:`Julien Jerphanion <jjerphan>` and :user:`Amanda Dsouza <amy12xx>`.

- |Enhancement| :func:`model_selection.cross_val_score`,
  :func:`model_selection.cross_validate`,
  :class:`model_selection.GridSearchCV`, and
  :class:`model_selection.RandomizedSearchCV` allows estimator to fail scoring
  and replace the score with `error_score`. If `error_score="raise"`, the error
  will be raised.
  :pr:`18343` by `Guillaume Lemaitre`_ and :user:`Devi Sandeep <dsandeep0138>`.

- |Enhancement| :func:`model_selection.learning_curve` now accept fit_params
  to pass additional estimator parameters.
  :pr:`18595` by :user:`Amanda Dsouza <amy12xx>`.

- |Fix| Fixed the `len` of :class:`model_selection.ParameterSampler` when
  all distributions are lists and `n_iter` is more than the number of unique
  parameter combinations. :pr:`18222` by `Nicolas Hug`_.

- |Fix| A fix to raise warning when one or more CV splits of
  :class:`model_selection.GridSearchCV` and
  :class:`model_selection.RandomizedSearchCV` results in non-finite scores.
  :pr:`18266` by :user:`Subrat Sahu <subrat93>`,
  :user:`Nirvan <Nirvan101>` and :user:`Arthur Book <ArthurBook>`.

- |Enhancement| :class:`model_selection.GridSearchCV`,
  :class:`model_selection.RandomizedSearchCV` and
  :func:`model_selection.cross_validate` support `scoring` being a callable
  returning a dictionary of of multiple metric names/values association.
  :pr:`15126` by `Thomas Fan`_.

:mod:`sklearn.multiclass`
.........................

- |Enhancement| :class:`multiclass.OneVsOneClassifier` now accepts
  the inputs with missing values. Hence, estimators which can handle
  missing values (may be a pipeline with imputation step) can be used as
  a estimator for multiclass wrappers.
  :pr:`17987` by :user:`Venkatachalam N <venkyyuvy>`.

- |Fix| A fix to allow :class:`multiclass.OutputCodeClassifier` to accept
  sparse input data in its `fit` and `predict` methods. The check for
  validity of the input is now delegated to the base estimator.
  :pr:`17233` by :user:`Zolisa Bleki <zoj613>`.

:mod:`sklearn.multioutput`
..........................

- |Enhancement| :class:`multioutput.MultiOutputClassifier` and
  :class:`multioutput.MultiOutputRegressor` now accepts the inputs
  with missing values. Hence, estimators which can handle missing
  values (may be a pipeline with imputation step, HistGradientBoosting
  estimators) can be used as a estimator for multiclass wrappers.
  :pr:`17987` by :user:`Venkatachalam N <venkyyuvy>`.

- |Fix| A fix to accept tuples for the ``order`` parameter
  in :class:`multioutput.ClassifierChain`.
  :pr:`18124` by :user:`Gus Brocchini <boldloop>` and
  :user:`Amanda Dsouza <amy12xx>`.

:mod:`sklearn.naive_bayes`
..........................

- |Enhancement| Adds a parameter `min_categories` to
  :class:`naive_bayes.CategoricalNB` that allows a minimum number of categories
  per feature to be specified. This allows categories unseen during training
  to be accounted for.
  :pr:`16326` by :user:`George Armstrong <gwarmstrong>`.

- |API| The attributes ``coef_`` and ``intercept_`` are now deprecated in
  :class:`naive_bayes.MultinomialNB`, :class:`naive_bayes.ComplementNB`,
  :class:`naive_bayes.BernoulliNB` and :class:`naive_bayes.CategoricalNB`,
  and will be removed in v1.1 (renaming of 0.26).
  :pr:`17427` by :user:`Juan Carlos Alfaro Jiménez <alfaro96>`.

:mod:`sklearn.neighbors`
........................

- |Efficiency| Speed up ``seuclidean``, ``wminkowski``, ``mahalanobis`` and
  ``haversine`` metrics in :class:`neighbors.DistanceMetric` by avoiding
  unexpected GIL acquiring in Cython when setting ``n_jobs>1`` in
  :class:`neighbors.KNeighborsClassifier`,
  :class:`neighbors.KNeighborsRegressor`,
  :class:`neighbors.RadiusNeighborsClassifier`,
  :class:`neighbors.RadiusNeighborsRegressor`,
  :func:`metrics.pairwise_distances`
  and by validating data out of loops.
  :pr:`17038` by :user:`Wenbo Zhao <webber26232>`.

- |Efficiency| :class:`neighbors.NeighborsBase` benefits of an improved
  `algorithm = 'auto'` heuristic. In addition to the previous set of rules,
  now, when the number of features exceeds 15, `brute` is selected, assuming
  the data intrinsic dimensionality is too high for tree-based methods.
  :pr:`17148` by :user:`Geoffrey Bolmier <gbolmier>`.

- |Fix| :class:`neighbors.BinaryTree`
  will raise a `ValueError` when fitting on data array having points with
  different dimensions.
  :pr:`18691` by :user:`Chiara Marmo <cmarmo>`.

- |Fix| :class:`neighbors.NearestCentroid` with a numerical `shrink_threshold`
  will raise a `ValueError` when fitting on data with all constant features.
  :pr:`18370` by :user:`Trevor Waite <trewaite>`.

- |Fix| In  methods `radius_neighbors` and
  `radius_neighbors_graph` of :class:`neighbors.NearestNeighbors`,
  :class:`neighbors.RadiusNeighborsClassifier`,
  :class:`neighbors.RadiusNeighborsRegressor`, and
  :class:`neighbors.RadiusNeighborsTransformer`, using `sort_results=True` now
  correctly sorts the results even when fitting with the "brute" algorithm.
  :pr:`18612` by `Tom Dupre la Tour`_.

:mod:`sklearn.neural_network`
.............................

- |Efficiency| Neural net training and prediction are now a little faster.
  :pr:`17603`, :pr:`17604`, :pr:`17606`, :pr:`17608`, :pr:`17609`, :pr:`17633`,
  :pr:`17661`, :pr:`17932` by :user:`Alex Henrie <alexhenrie>`.

- |Enhancement| Avoid converting float32 input to float64 in
  :class:`neural_network.BernoulliRBM`.
  :pr:`16352` by :user:`Arthur Imbert <Henley13>`.

- |Enhancement| Support 32-bit computations in
  :class:`neural_network.MLPClassifier` and
  :class:`neural_network.MLPRegressor`.
  :pr:`17759` by :user:`Srimukh Sripada <d3b0unce>`.

- |Fix| Fix method  :func:`fit` of :class:`neural_network.MLPClassifier`
  not iterating to ``max_iter`` if warm started.
  :pr:`18269` by :user:`Norbert Preining <norbusan>` and
  :user:`Guillaume Lemaitre <glemaitre>`.

:mod:`sklearn.pipeline`
.......................

- |Enhancement| References to transformers passed through ``transformer_weights``
  to :class:`pipeline.FeatureUnion` that aren't present in ``transformer_list``
  will raise a ``ValueError``.
  :pr:`17876` by :user:`Cary Goltermann <Ultramann>`.

- |Fix| A slice of a :class:`pipeline.Pipeline` now inherits the parameters of
  the original pipeline (`memory` and `verbose`).
  :pr:`18429` by :user:`Albert Villanova del Moral <albertvillanova>` and
  :user:`Paweł Biernat <pwl>`.

:mod:`sklearn.preprocessing`
............................

- |Feature| :class:`preprocessing.OneHotEncoder` now supports missing
  values by treating them as a category. :pr:`17317` by `Thomas Fan`_.

- |Feature| Add a new ``handle_unknown`` parameter with a
  ``use_encoded_value`` option, along with a new ``unknown_value`` parameter,
  to :class:`preprocessing.OrdinalEncoder` to allow unknown categories during
  transform and set the encoded value of the unknown categories.
  :pr:`17406` by :user:`Felix Wick <FelixWick>` and :pr:`18406` by
  `Nicolas Hug`_.

- |Feature| Add ``clip`` parameter to :class:`preprocessing.MinMaxScaler`,
  which clips the transformed values of test data to ``feature_range``.
  :pr:`17833` by :user:`Yashika Sharma <yashika51>`.

- |Feature| Add ``sample_weight`` parameter to
  :class:`preprocessing.StandardScaler`. Allows setting
  individual weights for each sample. :pr:`18510` and
  :pr:`18447` and :pr:`16066` and :pr:`18682` by
  :user:`Maria Telenczuk <maikia>` and :user:`Albert Villanova <albertvillanova>`
  and :user:`panpiort8` and :user:`Alex Gramfort <agramfort>`.

- |Enhancement| Verbose output of :class:`model_selection.GridSearchCV` has
  been improved for readability. :pr:`16935` by :user:`Raghav Rajagopalan
  <raghavrv>` and :user:`Chiara Marmo <cmarmo>`.

- |Enhancement| Add ``unit_variance`` to :class:`preprocessing.RobustScaler`,
  which scales output data such that normally distributed features have a
  variance of 1. :pr:`17193` by :user:`Lucy Liu <lucyleeow>` and
  :user:`Mabel Villalba <mabelvj>`.

- |Enhancement| Add `dtype` parameter to
  :class:`preprocessing.KBinsDiscretizer`.
  :pr:`16335` by :user:`Arthur Imbert <Henley13>`.

- |Fix| Raise error on
  :meth:`sklearn.preprocessing.OneHotEncoder.inverse_transform`
  when `handle_unknown='error'` and `drop=None` for samples
  encoded as all zeros. :pr:`14982` by
  :user:`Kevin Winata <kwinata>`.

:mod:`sklearn.semi_supervised`
..............................

- |MajorFeature| Added :class:`semi_supervised.SelfTrainingClassifier`, a
  meta-classifier that allows any supervised classifier to function as a
  semi-supervised classifier that can learn from unlabeled data. :issue:`11682`
  by :user:`Oliver Rausch <orausch>` and :user:`Patrice Becker <pr0duktiv>`.

- |Fix| Fix incorrect encoding when using unicode string dtypes in
  :class:`preprocessing.OneHotEncoder` and
  :class:`preprocessing.OrdinalEncoder`. :pr:`15763` by `Thomas Fan`_.

:mod:`sklearn.svm`
..................

- |Enhancement| invoke SciPy BLAS API for SVM kernel function in ``fit``,
  ``predict`` and related methods of :class:`svm.SVC`, :class:`svm.NuSVC`,
  :class:`svm.SVR`, :class:`svm.NuSVR`, :class:`OneClassSVM`.
  :pr:`16530` by :user:`Shuhua Fan <jim0421>`.

:mod:`sklearn.tree`
...................

- |Feature| :class:`tree.DecisionTreeRegressor` now supports the new splitting
  criterion ``'poisson'`` useful for modeling count data. :pr:`17386` by
  :user:`Christian Lorentzen <lorentzenchr>`.

- |Enhancement| :func:`tree.plot_tree` now uses colors from the matplotlib
  configuration settings. :pr:`17187` by `Andreas Müller`_.

- |API| The parameter ``X_idx_sorted`` is now deprecated in
  :meth:`tree.DecisionTreeClassifier.fit` and
  :meth:`tree.DecisionTreeRegressor.fit`, and has not effect.
  :pr:`17614` by :user:`Juan Carlos Alfaro Jiménez <alfaro96>`.

:mod:`sklearn.utils`
....................

- |Enhancement| Add ``check_methods_sample_order_invariance`` to
  :func:`~utils.estimator_checks.check_estimator`, which checks that
  estimator methods are invariant if applied to the same dataset
  with different sample order :pr:`17598` by :user:`Jason Ngo <ngojason9>`.

- |Enhancement| Add support for weights in
  :func:`utils.sparse_func.incr_mean_variance_axis`.
  By :user:`Maria Telenczuk <maikia>` and :user:`Alex Gramfort <agramfort>`.

- |Fix| Raise ValueError with clear error message in :func:`check_array`
  for sparse DataFrames with mixed types.
  :pr:`17992` by :user:`Thomas J. Fan <thomasjpfan>` and
  :user:`Alex Shacked <alexshacked>`.

- |Fix| Allow serialized tree based models to be unpickled on a machine
  with different endianness.
  :pr:`17644` by :user:`Qi Zhang <qzhang90>`.

- |Fix| Check that we raise proper error when axis=1 and the
  dimensions do not match in :func:`utils.sparse_func.incr_mean_variance_axis`.
  By :user:`Alex Gramfort <agramfort>`.

Miscellaneous
.............

- |Enhancement| Calls to ``repr`` are now faster
  when `print_changed_only=True`, especially with meta-estimators.
  :pr:`18508` by :user:`Nathan C. <Xethan>`.

Code and Documentation Contributors
-----------------------------------

Thanks to everyone who has contributed to the maintenance and improvement of
the project since version 0.23, including:

Abo7atm, Adam Spannbauer, Adrin Jalali, adrinjalali, Agamemnon Krasoulis,
Akshay Deodhar, Albert Villanova del Moral, Alessandro Gentile, Alex Henrie,
Alex Itkes, Alex Liang, Alexander Lenail, alexandracraciun, Alexandre Gramfort,
alexshacked, Allan D Butler, Amanda Dsouza, amy12xx, Anand Tiwari, Anderson
Nelson, Andreas Mueller, Ankit Choraria, Archana Subramaniyan, Arthur Imbert,
Ashutosh Hathidara, Ashutosh Kushwaha, Atsushi Nukariya, Aura Munoz, AutoViz
and Auto_ViML, Avi Gupta, Avinash Anakal, Ayako YAGI, barankarakus,
barberogaston, beatrizsmg, Ben Mainye, Benjamin Bossan, Benjamin Pedigo, Bharat
Raghunathan, Bhavika Devnani, Biprateep Dey, bmaisonn, Bo Chang, Boris
Villazón-Terrazas, brigi, Brigitta Sipőcz, Bruno Charron, Byron Smith, Cary
Goltermann, Cat Chenal, CeeThinwa, chaitanyamogal, Charles Patel, Chiara Marmo,
Christian Kastner, Christian Lorentzen, Christoph Deil, Christos Aridas, Clara
Matos, clmbst, Coelhudo, crispinlogan, Cristina Mulas, Daniel López, Daniel
Mohns, darioka, Darshan N, david-cortes, Declan O'Neill, Deeksha Madan,
Elizabeth DuPre, Eric Fiegel, Eric Larson, Erich Schubert, Erin Khoo, Erin R
Hoffman, eschibli, Felix Wick, fhaselbeck, Forrest Koch, Francesco Casalegno,
Frans Larsson, Gael Varoquaux, Gaurav Desai, Gaurav Sheni, genvalen, Geoffrey
Bolmier, George Armstrong, George Kiragu, Gesa Stupperich, Ghislain Antony
Vaillant, Gim Seng, Gordon Walsh, Gregory R. Lee, Guillaume Chevalier,
Guillaume Lemaitre, Haesun Park, Hannah Bohle, Hao Chun Chang, Harry Scholes,
Harsh Soni, Henry, Hirofumi Suzuki, Hitesh Somani, Hoda1394, Hugo Le Moine,
hugorichard, indecisiveuser, Isuru Fernando, Ivan Wiryadi, j0rd1smit, Jaehyun
Ahn, Jake Tae, James Hoctor, Jan Vesely, Jeevan Anand Anne, JeroenPeterBos,
JHayes, Jiaxiang, Jie Zheng, Jigna Panchal, jim0421, Jin Li, Joaquin
Vanschoren, Joel Nothman, Jona Sassenhagen, Jonathan, Jorge Gorbe Moya, Joseph
Lucas, Joshua Newton, Juan Carlos Alfaro Jiménez, Julien Jerphanion, Justin
Huber, Jérémie du Boisberranger, Kartik Chugh, Katarina Slama, kaylani2,
Kendrick Cetina, Kenny Huynh, Kevin Markham, Kevin Winata, Kiril Isakov,
kishimoto, Koki Nishihara, Krum Arnaudov, Kyle Kosic, Lauren Oldja, Laurenz
Reitsam, Lisa Schwetlick, Louis Douge, Louis Guitton, Lucy Liu, Madhura
Jayaratne, maikia, Manimaran, Manuel López-Ibáñez, Maren Westermann, Maria
Telenczuk, Mariam-ke, Marijn van Vliet, Markus Löning, Martin Scheubrein,
Martina G. Vilas, Martina Megasari, Mateusz Górski, mathschy, mathurinm,
Matthias Bussonnier, Max Del Giudice, Michael, Milan Straka, Muoki Caleb, N.
Haiat, Nadia Tahiri, Ph. D, Naoki Hamada, Neil Botelho, Nicolas Hug, Nils
Werner, noelano, Norbert Preining, oj_lappi, Oleh Kozynets, Olivier Grisel,
Pankaj Jindal, Pardeep Singh, Parthiv Chigurupati, Patrice Becker, Pete Green,
pgithubs, Poorna Kumar, Prabakaran Kumaresshan, Probinette4, pspachtholz,
pwalchessen, Qi Zhang, rachel fischoff, Rachit Toshniwal, Rafey Iqbal Rahman,
Rahul Jakhar, Ram Rachum, RamyaNP, rauwuckl, Ravi Kiran Boggavarapu, Ray Bell,
Reshama Shaikh, Richard Decal, Rishi Advani, Rithvik Rao, Rob Romijnders, roei,
Romain Tavenard, Roman Yurchak, Ruby Werman, Ryotaro Tsukada, sadak, Saket
Khandelwal, Sam, Sam Ezebunandu, Sam Kimbinyi, Sarah Brown, Saurabh Jain, Sean
O. Stalley, Sergio, Shail Shah, Shane Keller, Shao Yang Hong, Shashank Singh,
Shooter23, Shubhanshu Mishra, simonamaggio, Soledad Galli, Srimukh Sripada,
Stephan Steinfurt, subrat93, Sunitha Selvan, Swier, Sylvain Marié, SylvainLan,
t-kusanagi2, Teon L Brooks, Terence Honles, Thijs van den Berg, Thomas J Fan,
Thomas J. Fan, Thomas S Benjamin, Thomas9292, Thorben Jensen, tijanajovanovic,
Timo Kaufmann, tnwei, Tom Dupré la Tour, Trevor Waite, ufmayer, Umberto Lupo,
Venkatachalam N, Vikas Pandey, Vinicius Rios Fuck, Violeta, watchtheblur, Wenbo
Zhao, willpeppo, xavier dupré, Xethan, Xue Qianming, xun-tang, yagi-3, Yakov
Pchelintsev, Yashika Sharma, Yi-Yan Ge, Yue Wu, Yutaro Ikeda, Zaccharie Ramzi,
zoj613, Zhao Feng.