SklearnClassifierPipeline

class SklearnClassifierPipeline(classifier, transformers)

Pipeline of transformers and a classifier.

The SklearnClassifierPipeline chains transformers and an single classifier.

Similar to ClassifierPipeline, but uses a tabular sklearn classifier.

The pipeline is constructed with a list of aeon transformers, plus a classifier,

i.e., transformers following the BaseTransformer interface, classifier follows the scikit-learn classifier interface.

The transformer list can be unnamed - a simple list of transformers -

or string named - a list of pairs of string, estimator.

For a list of transformers trafo1, trafo2, …, trafoN and a classifier clf,

the pipeline behaves as follows:

fit(X, y) - changes styte by running trafo1.fit_transform on X,

them trafo2.fit_transform on the output of trafo1.fit_transform, etc sequentially, with trafo[i] receiving the output of trafo[i-1], and then running clf.fit with X the output of trafo[N] converted to numpy, and y identical with the input to self.fit. X is converted to numpyflat mtype if X is of Panel scitype; X is converted to numpy2D mtype if X is of Table scitype.

predict(X) - result is of executing trafo1.transform, trafo2.transform, etc

with trafo[i].transform input = output of trafo[i-1].transform, then running clf.predict on the numpy converted output of trafoN.transform, and returning the output of clf.predict. Output of trasfoN.transform is converted to numpy, as in fit.

predict_proba(X) - result is of executing trafo1.transform, trafo2.transform,

etc, with trafo[i].transform input = output of trafo[i-1].transform, then running clf.predict_proba on the output of trafoN.transform, and returning the output of clf.predict_proba. Output of trasfoN.transform is converted to numpy, as in fit.

get_params, set_params uses sklearn compatible nesting interface

if list is unnamed, names are generated as names of classes if names are non-unique, f”_{str(i)}” is appended to each name string

where i is the total count of occurrence of a non-unique string inside the list of names leading up to it (inclusive)

SklearnClassifierPipeline can also be created by using the magic multiplication

between aeon transformers and sklearn classifiers,

and my_trafo1, my_trafo2 inherit from BaseTransformer, then, for instance, my_trafo1 * my_trafo2 * my_clf will result in the same object as obtained from the constructor SklearnClassifierPipeline(classifier=my_clf, transformers=[t1, t2])

magic multiplication can also be used with (str, transformer) pairs,

as long as one element in the chain is a transformer

Parameters:

classifiersklearn classifier, i.e., inheriting from sklearn ClassifierMixin

this is a “blueprint” classifier, state does not change when fit is called

transformerslist of aeon transformers, or

list of tuples (str, transformer) of aeon transformers these are “blueprint” transformers, states do not change when fit is called

Attributes:

classifier_sklearn classifier, clone of classifier in classifier

this clone is fitted in the pipeline when fit is called

transformers_list of tuples (str, transformer) of aeon transformers

clones of transformers in transformers which are fitted in the pipeline is always in (str, transformer) format, even if transformers is just a list strings not passed in transformers are unique generated strings i-th transformer in transformers_ is clone of i-th in transformers

Examples

>>> from sklearn.neighbors import KNeighborsClassifier
>>> from aeon.transformations.series.exponent import ExponentTransformer
>>> from aeon.transformations.series.summarize import SummaryTransformer
>>> from aeon.datasets import load_unit_test
>>> from aeon.classification.compose import SklearnClassifierPipeline
>>> X_train, y_train = load_unit_test(split="train")
>>> X_test, y_test = load_unit_test(split="test")
>>> t1 = ExponentTransformer()
>>> t2 = SummaryTransformer()
>>> pipeline = SklearnClassifierPipeline(KNeighborsClassifier(), [t1, t2])
>>> pipeline = pipeline.fit(X_train, y_train)
>>> y_pred = pipeline.predict(X_test)

Methods

check_is_fitted()	Check if the estimator has been fitted.
clone()	Obtain a clone of the object with same hyper-parameters.
clone_tags(estimator[, tag_names])	clone/mirror tags from another estimator as dynamic override.
create_test_instance([parameter_set])	Construct Estimator instance if possible.
create_test_instances_and_names([parameter_set])	Create list of all test instances and a list of names for them.
fit(X, y)	Fit time series classifier to training data.
get_class_tag(tag_name[, tag_value_default])	Get tag value from estimator class (only class tags).
get_class_tags()	Get class tags from estimator class and all its parent classes.
get_fitted_params([deep])	Get fitted parameters.
get_param_defaults()	Get parameter defaults for the object.
get_param_names()	Get parameter names for the object.
get_params([deep])	Get parameters of estimator in transformers.
get_tag(tag_name[, tag_value_default, ...])	Get tag value from estimator class and dynamic tag overrides.
get_tags()	Get tags from estimator class and dynamic tag overrides.
get_test_params([parameter_set])	Return testing parameter settings for the estimator.
is_composite()	Check if the object is composite.
load_from_path(serial)	Load object from file location.
load_from_serial(serial)	Load object from serialized memory container.
predict(X)	Predicts labels for time series in X.
predict_proba(X)	Predicts labels probabilities for sequences in X.
reset()	Reset the object to a clean post-init state.
save([path])	Save serialized self to bytes-like object or to (.zip) file.
score(X, y)	Scores predicted labels against ground truth labels on X.
set_params(**kwargs)	Set the parameters of estimator in transformers.
set_tags(**tag_dict)	Set dynamic tags to given values.

clone()

Obtain a clone of the object with same hyper-parameters.

A clone is a different object without shared references, in post-init state. This function is equivalent to returning sklearn.clone of self. Equal in value to type(self)(**self.get_params(deep=False)).

Returns:

instance of type(self), clone of self (see above)

get_params(deep=True)

Get parameters of estimator in transformers.

Parameters:

deepboolean, optional, default=True

If True, will return the parameters for this estimator and contained sub-objects that are estimators.

Returns:

paramsmapping of string to any

Parameter names mapped to their values.

check_is_fitted()

Check if the estimator has been fitted.

Raises:

NotFittedError

If the estimator has not been fitted yet.

clone_tags(estimator, tag_names=None)

clone/mirror tags from another estimator as dynamic override.

Parameters:

estimatorestimator inheriting from :class:BaseEstimator

tag_namesstr or list of str, default = None

Names of tags to clone. If None then all tags in estimator are used as tag_names.

Returns:

Self

Reference to self.

Notes

Changes object state by setting tag values in tag_set from estimator as dynamic tags in self.

classmethod create_test_instance(parameter_set='default')

Construct Estimator instance if possible.

Parameters:

parameter_setstr, default=”default”

Name of the set of test parameters to return, for use in tests. If no special parameters are defined for a value, will return “default” set.

Returns:

instanceinstance of the class with default parameters

Notes

get_test_params can return dict or list of dict. This function takes first or single dict that get_test_params returns, and constructs the object with that.

classmethod create_test_instances_and_names(parameter_set='default')

Create list of all test instances and a list of names for them.

Parameters:

parameter_setstr, default=”default”

Name of the set of test parameters to return, for use in tests. If no special parameters are defined for a value, will return “default” set.

Returns:

objslist of instances of cls

i-th instance is cls(**cls.get_test_params()[i])

nameslist of str, same length as objs

i-th element is name of i-th instance of obj in tests convention is {cls.__name__}-{i} if more than one instance otherwise {cls.__name__}

parameter_setstr, default=”default”

Name of the set of test parameters to return, for use in tests. If no special parameters are defined for a value, will return “default” set.

fit(X, y)

Fit time series classifier to training data.

Parameters:

X3D np.array (any number of channels, equal length series)

of shape [n_instances, n_channels, series_length]

or 2D np.array (univariate, equal length series)

of shape [n_instances, series_length]

y1D np.array of int, of shape [n_instances] - class labels for fitting

indices correspond to instance indices in X

Returns:

selfReference to self.

Notes

Changes state by creating a fitted model that updates attributes ending in “_” and sets is_fitted flag to True.

classmethod get_class_tag(tag_name, tag_value_default=None)

Get tag value from estimator class (only class tags).

Parameters:

tag_namestr

Name of tag value.

tag_value_defaultany type

Default/fallback value if tag is not found.

Returns:

tag_value

Value of the tag_name tag in self. If not found, returns tag_value_default.

classmethod get_class_tags()

Get class tags from estimator class and all its parent classes.

Returns:

collected_tagsdict

Dictionary of tag name : tag value pairs. Collected from _tags class attribute via nested inheritance. NOT overridden by dynamic tags set by set_tags or mirror_tags.

get_fitted_params(deep=True)

Get fitted parameters.

State required:

Requires state to be “fitted”.

Parameters:

deepbool, default=True

Whether to return fitted parameters of components.

• If True, will return a dict of parameter name : value for this object, including fitted parameters of fittable components (= BaseEstimator-valued parameters).

• If False, will return a dict of parameter name : value for this object, but not include fitted parameters of components.

Returns:

fitted_paramsdict with str-valued keys

Dictionary of fitted parameters, paramname : paramvalue keys-value pairs include:

• always: all fitted parameters of this object, as via get_param_names values are fitted parameter value for that key, of this object

• if deep=True, also contains keys/value pairs of component parameters parameters of components are indexed as [componentname]__[paramname] all parameters of componentname appear as paramname with its value

• if deep=True, also contains arbitrary levels of component recursion, e.g., [componentname]__[componentcomponentname]__[paramname], etc

classmethod get_param_defaults()

Get parameter defaults for the object.

Returns:

default_dict: dict with str keys

keys are all parameters of cls that have a default defined in __init__ values are the defaults, as defined in __init__

classmethod get_param_names()

Get parameter names for the object.

Returns:

param_names: list of str, alphabetically sorted list of parameter names of cls

get_tag(tag_name, tag_value_default=None, raise_error=True)

Get tag value from estimator class and dynamic tag overrides.

Parameters:

tag_namestr

Name of tag to be retrieved

tag_value_defaultany type, optional; default=None

Default/fallback value if tag is not found

raise_errorbool

whether a ValueError is raised when the tag is not found

Returns:

tag_value

Value of the tag_name tag in self. If not found, returns an error if raise_error is True, otherwise it returns tag_value_default.

Raises:

ValueError if raise_error is True i.e. if tag_name is not in self.get_tags(

).keys()

get_tags()

Get tags from estimator class and dynamic tag overrides.

Returns:

collected_tagsdict

Dictionary of tag name : tag value pairs. Collected from _tags class attribute via nested inheritance and then any overrides and new tags from _tags_dynamic object attribute.

is_composite()

Check if the object is composite.

A composite object is an object which contains objects, as parameters. Called on an instance, since this may differ by instance.

Returns:

composite: bool, whether self contains a parameter which is BaseObject

property is_fitted

Whether fit has been called.

classmethod load_from_path(serial)

Load object from file location.

Parameters:

serialresult of ZipFile(path).open(“object)

Returns:

deserialized self resulting in output at path, of cls.save(path)

classmethod load_from_serial(serial)

Load object from serialized memory container.

Parameters:

serial1st element of output of cls.save(None)

Returns:

deserialized self resulting in output serial, of cls.save(None)

predict(X) → ndarray

Predicts labels for time series in X.

Parameters:

X3D np.array of shape (n_instances, n_channels, series_length)

or 2D np.array of shape (n_instances, series_length)

Returns:

y1D np.array of int, of shape [n_instances] - predicted class labels

indices correspond to instance indices in X

predict_proba(X) → ndarray

Predicts labels probabilities for sequences in X.

Parameters:

X3D np.array of shape (n_cases, n_channels, series_length)

or 2D np.array of shape (n_cases, series_length)

Returns:

y2D array of shape (n_cases, n_classes) - predicted class probabilities

First dimension indices correspond to instance indices in X, second dimension indices correspond to class labels, (i, j)-th entry is estimated probability that i-th instance is of class j

reset()

Reset the object to a clean post-init state.

Equivalent to sklearn.clone but overwrites self. After self.reset() call, self is equal in value to type(self)(**self.get_params(deep=False))

Detail behaviour: removes any object attributes, except:

hyper-parameters = arguments of __init__ object attributes containing double-underscores, i.e., the string “__”

runs __init__ with current values of hyper-parameters (result of get_params)

Not affected by the reset are: object attributes containing double-underscores class and object methods, class attributes

save(path=None)

Save serialized self to bytes-like object or to (.zip) file.

Behaviour: if path is None, returns an in-memory serialized self if path is a file location, stores self at that location as a zip file

saved files are zip files with following contents: _metadata - contains class of self, i.e., type(self) _obj - serialized self. This class uses the default serialization (pickle).

Parameters:

pathNone or file location (str or Path)

if None, self is saved to an in-memory object if file location, self is saved to that file location. If:

path=”estimator” then a zip file estimator.zip will be made at cwd. path=”/home/stored/estimator” then a zip file estimator.zip will be stored in /home/stored/.

Returns:

if path is None - in-memory serialized self

if path is file location - ZipFile with reference to the file

score(X, y) → float

Scores predicted labels against ground truth labels on X.

Parameters:

X3D np.array (any number of channels, equal length series)

of shape [n_instances, n_channels, series_length]

or 2D np.array (univariate, equal length series)

of shape [n_instances, series_length]

y1D np.ndarray of shape [n_instances] - class labels (ground truth)

indices correspond to instance indices in X

Returns:

float, accuracy score of predict(X) vs y

set_params(**kwargs)

Set the parameters of estimator in transformers.

Valid parameter keys can be listed with get_params().

Returns:

selfreturns an instance of self.

set_tags(**tag_dict)

Set dynamic tags to given values.

Parameters:

tag_dictdict

Dictionary of tag name : tag value pairs.

Returns:

Self

Reference to self.

Notes

Changes object state by settting tag values in tag_dict as dynamic tags in self.

classmethod get_test_params(parameter_set='default')

Return testing parameter settings for the estimator.

Parameters:

parameter_setstr, default=”default”

Name of the set of test parameters to return, for use in tests. If no special parameters are defined for a value, will return “default” set.

Returns:

paramsdict or list of dict, default={}

Parameters to create testing instances of the class. Each dict are parameters to construct an “interesting” test instance, i.e., MyClass(**params) or MyClass(**params[i]) creates a valid test instance. create_test_instance uses the first (or only) dictionary in params.