* Fixed typo in an example
* Removed un-needed lines from example
* Added tests on the validity of parameters
* Fixed error msg for train_size issue
* Added tests to check the validation of test and train sizes
* Switched to parameterized test
* Fixed typo in error msg
* Swithced to pytest.raises
* Swithced to pytest.raises also when checking msg
* Improved the validity tests and their unit testing
#### Reference Issues/PRs
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This PR addresses issue #12466.
#### What does this implement/fix? Explain your changes.
This PR does the 3 following things:
- Rewrite the `cv` parameter description in `GridSearchCV`
- Link the new `CV splitter` description to an existing example
- Add an example with a custom iterable
Thanks for reviewing this!
Close#12466
* add FutureWarning for methods with defaults=3
* add explicit cv values to fix assertion errors
* add tests for catching the FutureWarning
* Write current deprecation version
* Add deprecation in docstring
* change default cv value to None
* change cv from 3 to 5 in the examples
* upgrade doctests
* update doctest in tutorial
* update doctest in cross-validation doc
* fix tests
* add entry to whats new
* address Gael comments
* address Gael comments 2
* fix wrong indentation
* update doc
* add docstring deprecation warning in CV subclasses
* address Andy's comments
* fix PR number
* fix flake8
* add filterwarnings in tests
* fix doctests
* cv=None mendatory in Ridge
* fix warning related errors
* skip some doctests warnings
* make travis happy
* change from deprecated to versionchanged
* fix doctests and remove skipping
* address comments
Closes https://github.com/scikit-learn/scikit-learn/issues/11121
This PR removes the deprecation warning about ABC being moved from `collections` to `collections.abc` when importing scikit-learn in Python 3.7.
In the end, I put `collections.abc.{Sequence, Iterable, Mapping, Sized}` in the namespace of `sklearn.utils.fixes`. This was the simplest way I could find, and while it has the drawback of obfuscating the real module name, other approached appeared more problematic and a similar approach is currently used e.g. for `utils.fixes.signature` which is an alias for `inspect.signature`.
We can't just patch six with https://github.com/benjaminp/six/pull/241, because sklearn uses six from 5 years ago, which would need updating and I'm not sure if it could have side effects (e.g. for pickling backward compatibility etc).
**Edit**: This adds a test checking that generally no warnings are raised when importing scikit-learn top-level modules.
* Use ' '.join(row) for multi-label targets in StratifiedShuffleSplit because str(row) uses an ellipsis when len(row) > 1000
* Add a new test for multilabel problems with more than a thousand labels
* rm dupes
* add check_supervised_y_no_nan in classifier checks: this implies changes for Ridge classifiers
* fix docstrings/comments
* FIX check fitting 1d X array raises error and FIX check fitting 2d array with only 1 feature either works or returns informative message
* modify check_fit2d_1sample in common tests so that it checks fitting either works or returns an informative message
* rm SpectralClustering case for the moment
* uniformize error messages for 1 sample case and fix SpectralClustering with ensure_min_samples=2
* add unit test for mean_shift when n_samples * quantile < 1
* FIX travis with ensure_min_samples=2 in _PLS
* try fix for failing tSNE test
* typos
* take @agramfort's review into account
* sc to fix string in gaussian_process
* add the class that is present to preserve information of previous message in gpc.py
* Adding parameter information to docstring.
* Removing trailing whitespace from lines.
* Adding details of parameter to formal Parameters section.
* Shortened lines to meet requirements.
* DOC Add NOTE that unless random_state is set, split will not be identical
* TST use np.testing.assert_equal for nested lists/arrays
* TST Make sure cv param can be a generator
* DOC rank_ becomes a link when rendered
* Use test_...
* Remove blank line; Add if shuffle is True
* Fix tests
* Explicitly test for GeneratorType
* TST Add the else clause
* TST Add comment on usage of np.testing.assert_array_equal
* TYPO
* MNT Remove if ;
* Address Joel's comments
* merge the identical points in doc
* DOC address Andy's comments
* Move comment to before the check for generator type
* regression test and fix for 2d stratified shuffle split
* strengthen non-overlap sss tests
* clarify test and comment
* remove iter from tests, use str instead of hash
* add shuffle paramater to train_test_split
* fix syntax error
* fix variable name
* fix formatting in doctest output
* fix doctest output
* refactor shuffle paramater into ShuffleSplit and StratifiedShuffleSplit
* include shuffle option in tests
* rollback refactor
* revert to simpler version of unshuffled split
* fix flake8 errors
* revert changes to ShuffleSplit
* revert BaseShuffleSplit
* more reversions
* fix indentation
* remove shuffle parameter from CVclass
* add text to NotImplementedError
* change indexing to use numpy.arange rather than range
* specify precondition for stratify to be None in docstring
* remove needless argument checking
* add parameter checking as in LeavePGroupsOut
* add examples with dummy inputs
* add unittest for a get_n_splits method in LeaveOneGroupOut and LeavePGroupsOut classes
* X and y can be ommited in a get_n_splits function.
* fix error messages
* update examples
* fix test for an error message
* Revert "fix test for an error message"
This reverts commit 68b984207c.
* fix test for an error message
* fix error messages
* remove tailing white spaces
* add periods to messages
* test for ValueError’s of get_n_splits methods of LeaveOneOut / LeavePOut classes
* fix documents:
* parameter name: group -> groups
* modfy white space
* Add _RepeatedSplits and RepeatedKFold class
* Add RepeatedStratifiedKFold and doc for repeated cvs
* Change default value of n_repeats
* Change input parameters of repeated cv constructor to n_splits, n_repeats, random_state
* Generate random states in split function rather than store it beforehand
* Doc changes, inheriting RepeatedKFold, RepeatedStratifiedKFold from _RepeatedSplits and other review changes
* Remove blank line, put testcases for deterministic split in loop and add StopIteration check in testcase
* Using rng directly as random_state param to create cv instance and added a check for cvargs
* Fix pep8 warnings
* Changing default values for n_splits and n_repeats and add entry in changelog
* Adding name to the feature
* Missing space
* DOC Add whatnew for the 3 mod-sel bugfixes
* Move to 0.18.1; Change name universally to Raghav RV
* Raghav R V --> Raghav RV
* Edit mailmap to include my other email
Prabakaran Kumaresshan
Hanmin Qin