685 lines
23 KiB
Python
685 lines
23 KiB
Python
|
"""
|
||
|
|
Base classes for all estimators.
|
||
|
|
|
||
|
|
Used for VotingClassifier
|
||
|
|
"""
|
||
|
|
|
||
|
|
# Author: Gael Varoquaux <gael.varoquaux@normalesup.org>
|
||
|
|
# License: BSD 3 clause
|
||
|
|
|
||
|
|
import copy
|
||
|
|
import warnings
|
||
|
|
from collections import defaultdict
|
||
|
|
import platform
|
||
|
|
import inspect
|
||
|
|
import re
|
||
|
|
|
||
|
|
import numpy as np
|
||
|
|
|
||
|
|
from . import __version__
|
||
|
|
from .utils import _IS_32BIT
|
||
|
|
|
||
|
|
_DEFAULT_TAGS = {
|
||
|
|
'non_deterministic': False,
|
||
|
|
'requires_positive_X': False,
|
||
|
|
'requires_positive_y': False,
|
||
|
|
'X_types': ['2darray'],
|
||
|
|
'poor_score': False,
|
||
|
|
'no_validation': False,
|
||
|
|
'multioutput': False,
|
||
|
|
"allow_nan": False,
|
||
|
|
'stateless': False,
|
||
|
|
'multilabel': False,
|
||
|
|
'_skip_test': False,
|
||
|
|
'multioutput_only': False,
|
||
|
|
'binary_only': False,
|
||
|
|
'requires_fit': True}
|
||
|
|
|
||
|
|
|
||
|
|
def clone(estimator, safe=True):
|
||
|
|
"""Constructs a new estimator with the same parameters.
|
||
|
|
|
||
|
|
Clone does a deep copy of the model in an estimator
|
||
|
|
without actually copying attached data. It yields a new estimator
|
||
|
|
with the same parameters that has not been fit on any data.
|
||
|
|
|
||
|
|
Parameters
|
||
|
|
----------
|
||
|
|
estimator : estimator object, or list, tuple or set of objects
|
||
|
|
The estimator or group of estimators to be cloned
|
||
|
|
|
||
|
|
safe : boolean, optional
|
||
|
|
If safe is false, clone will fall back to a deep copy on objects
|
||
|
|
that are not estimators.
|
||
|
|
|
||
|
|
"""
|
||
|
|
estimator_type = type(estimator)
|
||
|
|
# XXX: not handling dictionaries
|
||
|
|
if estimator_type in (list, tuple, set, frozenset):
|
||
|
|
return estimator_type([clone(e, safe=safe) for e in estimator])
|
||
|
|
elif not hasattr(estimator, 'get_params') or isinstance(estimator, type):
|
||
|
|
if not safe:
|
||
|
|
return copy.deepcopy(estimator)
|
||
|
|
else:
|
||
|
|
raise TypeError("Cannot clone object '%s' (type %s): "
|
||
|
|
"it does not seem to be a scikit-learn estimator "
|
||
|
|
"as it does not implement a 'get_params' methods."
|
||
|
|
% (repr(estimator), type(estimator)))
|
||
|
|
klass = estimator.__class__
|
||
|
|
new_object_params = estimator.get_params(deep=False)
|
||
|
|
for name, param in new_object_params.items():
|
||
|
|
new_object_params[name] = clone(param, safe=False)
|
||
|
|
new_object = klass(**new_object_params)
|
||
|
|
params_set = new_object.get_params(deep=False)
|
||
|
|
|
||
|
|
# quick sanity check of the parameters of the clone
|
||
|
|
for name in new_object_params:
|
||
|
|
param1 = new_object_params[name]
|
||
|
|
param2 = params_set[name]
|
||
|
|
if param1 is not param2:
|
||
|
|
raise RuntimeError('Cannot clone object %s, as the constructor '
|
||
|
|
'either does not set or modifies parameter %s' %
|
||
|
|
(estimator, name))
|
||
|
|
return new_object
|
||
|
|
|
||
|
|
|
||
|
|
def _pprint(params, offset=0, printer=repr):
|
||
|
|
"""Pretty print the dictionary 'params'
|
||
|
|
|
||
|
|
Parameters
|
||
|
|
----------
|
||
|
|
params : dict
|
||
|
|
The dictionary to pretty print
|
||
|
|
|
||
|
|
offset : int
|
||
|
|
The offset in characters to add at the begin of each line.
|
||
|
|
|
||
|
|
printer : callable
|
||
|
|
The function to convert entries to strings, typically
|
||
|
|
the builtin str or repr
|
||
|
|
|
||
|
|
"""
|
||
|
|
# Do a multi-line justified repr:
|
||
|
|
options = np.get_printoptions()
|
||
|
|
np.set_printoptions(precision=5, threshold=64, edgeitems=2)
|
||
|
|
params_list = list()
|
||
|
|
this_line_length = offset
|
||
|
|
line_sep = ',\n' + (1 + offset // 2) * ' '
|
||
|
|
for i, (k, v) in enumerate(sorted(params.items())):
|
||
|
|
if type(v) is float:
|
||
|
|
# use str for representing floating point numbers
|
||
|
|
# this way we get consistent representation across
|
||
|
|
# architectures and versions.
|
||
|
|
this_repr = '%s=%s' % (k, str(v))
|
||
|
|
else:
|
||
|
|
# use repr of the rest
|
||
|
|
this_repr = '%s=%s' % (k, printer(v))
|
||
|
|
if len(this_repr) > 500:
|
||
|
|
this_repr = this_repr[:300] + '...' + this_repr[-100:]
|
||
|
|
if i > 0:
|
||
|
|
if (this_line_length + len(this_repr) >= 75 or '\n' in this_repr):
|
||
|
|
params_list.append(line_sep)
|
||
|
|
this_line_length = len(line_sep)
|
||
|
|
else:
|
||
|
|
params_list.append(', ')
|
||
|
|
this_line_length += 2
|
||
|
|
params_list.append(this_repr)
|
||
|
|
this_line_length += len(this_repr)
|
||
|
|
|
||
|
|
np.set_printoptions(**options)
|
||
|
|
lines = ''.join(params_list)
|
||
|
|
# Strip trailing space to avoid nightmare in doctests
|
||
|
|
lines = '\n'.join(l.rstrip(' ') for l in lines.split('\n'))
|
||
|
|
return lines
|
||
|
|
|
||
|
|
|
||
|
|
class BaseEstimator:
|
||
|
|
"""Base class for all estimators in scikit-learn
|
||
|
|
|
||
|
|
Notes
|
||
|
|
-----
|
||
|
|
All estimators should specify all the parameters that can be set
|
||
|
|
at the class level in their ``__init__`` as explicit keyword
|
||
|
|
arguments (no ``*args`` or ``**kwargs``).
|
||
|
|
"""
|
||
|
|
|
||
|
|
@classmethod
|
||
|
|
def _get_param_names(cls):
|
||
|
|
"""Get parameter names for the estimator"""
|
||
|
|
# fetch the constructor or the original constructor before
|
||
|
|
# deprecation wrapping if any
|
||
|
|
init = getattr(cls.__init__, 'deprecated_original', cls.__init__)
|
||
|
|
if init is object.__init__:
|
||
|
|
# No explicit constructor to introspect
|
||
|
|
return []
|
||
|
|
|
||
|
|
# introspect the constructor arguments to find the model parameters
|
||
|
|
# to represent
|
||
|
|
init_signature = inspect.signature(init)
|
||
|
|
# Consider the constructor parameters excluding 'self'
|
||
|
|
parameters = [p for p in init_signature.parameters.values()
|
||
|
|
if p.name != 'self' and p.kind != p.VAR_KEYWORD]
|
||
|
|
for p in parameters:
|
||
|
|
if p.kind == p.VAR_POSITIONAL:
|
||
|
|
raise RuntimeError("scikit-learn estimators should always "
|
||
|
|
"specify their parameters in the signature"
|
||
|
|
" of their __init__ (no varargs)."
|
||
|
|
" %s with constructor %s doesn't "
|
||
|
|
" follow this convention."
|
||
|
|
% (cls, init_signature))
|
||
|
|
# Extract and sort argument names excluding 'self'
|
||
|
|
return sorted([p.name for p in parameters])
|
||
|
|
|
||
|
|
def get_params(self, deep=True):
|
||
|
|
"""
|
||
|
|
Get parameters for this estimator.
|
||
|
|
|
||
|
|
Parameters
|
||
|
|
----------
|
||
|
|
deep : bool, default=True
|
||
|
|
If True, will return the parameters for this estimator and
|
||
|
|
contained subobjects that are estimators.
|
||
|
|
|
||
|
|
Returns
|
||
|
|
-------
|
||
|
|
params : mapping of string to any
|
||
|
|
Parameter names mapped to their values.
|
||
|
|
"""
|
||
|
|
out = dict()
|
||
|
|
for key in self._get_param_names():
|
||
|
|
try:
|
||
|
|
value = getattr(self, key)
|
||
|
|
except AttributeError:
|
||
|
|
warnings.warn('From version 0.24, get_params will raise an '
|
||
|
|
'AttributeError if a parameter cannot be '
|
||
|
|
'retrieved as an instance attribute. Previously '
|
||
|
|
'it would return None.',
|
||
|
|
FutureWarning)
|
||
|
|
value = None
|
||
|
|
if deep and hasattr(value, 'get_params'):
|
||
|
|
deep_items = value.get_params().items()
|
||
|
|
out.update((key + '__' + k, val) for k, val in deep_items)
|
||
|
|
out[key] = value
|
||
|
|
return out
|
||
|
|
|
||
|
|
def set_params(self, **params):
|
||
|
|
"""
|
||
|
|
Set the parameters of this estimator.
|
||
|
|
|
||
|
|
The method works on simple estimators as well as on nested objects
|
||
|
|
(such as pipelines). The latter have parameters of the form
|
||
|
|
``<component>__<parameter>`` so that it's possible to update each
|
||
|
|
component of a nested object.
|
||
|
|
|
||
|
|
Parameters
|
||
|
|
----------
|
||
|
|
**params : dict
|
||
|
|
Estimator parameters.
|
||
|
|
|
||
|
|
Returns
|
||
|
|
-------
|
||
|
|
self : object
|
||
|
|
Estimator instance.
|
||
|
|
"""
|
||
|
|
if not params:
|
||
|
|
# Simple optimization to gain speed (inspect is slow)
|
||
|
|
return self
|
||
|
|
valid_params = self.get_params(deep=True)
|
||
|
|
|
||
|
|
nested_params = defaultdict(dict) # grouped by prefix
|
||
|
|
for key, value in params.items():
|
||
|
|
key, delim, sub_key = key.partition('__')
|
||
|
|
if key not in valid_params:
|
||
|
|
raise ValueError('Invalid parameter %s for estimator %s. '
|
||
|
|
'Check the list of available parameters '
|
||
|
|
'with `estimator.get_params().keys()`.' %
|
||
|
|
(key, self))
|
||
|
|
|
||
|
|
if delim:
|
||
|
|
nested_params[key][sub_key] = value
|
||
|
|
else:
|
||
|
|
setattr(self, key, value)
|
||
|
|
valid_params[key] = value
|
||
|
|
|
||
|
|
for key, sub_params in nested_params.items():
|
||
|
|
valid_params[key].set_params(**sub_params)
|
||
|
|
|
||
|
|
return self
|
||
|
|
|
||
|
|
def __repr__(self, N_CHAR_MAX=700):
|
||
|
|
# N_CHAR_MAX is the (approximate) maximum number of non-blank
|
||
|
|
# characters to render. We pass it as an optional parameter to ease
|
||
|
|
# the tests.
|
||
|
|
|
||
|
|
from .utils._pprint import _EstimatorPrettyPrinter
|
||
|
|
|
||
|
|
N_MAX_ELEMENTS_TO_SHOW = 30 # number of elements to show in sequences
|
||
|
|
|
||
|
|
# use ellipsis for sequences with a lot of elements
|
||
|
|
pp = _EstimatorPrettyPrinter(
|
||
|
|
compact=True, indent=1, indent_at_name=True,
|
||
|
|
n_max_elements_to_show=N_MAX_ELEMENTS_TO_SHOW)
|
||
|
|
|
||
|
|
repr_ = pp.pformat(self)
|
||
|
|
|
||
|
|
# Use bruteforce ellipsis when there are a lot of non-blank characters
|
||
|
|
n_nonblank = len(''.join(repr_.split()))
|
||
|
|
if n_nonblank > N_CHAR_MAX:
|
||
|
|
lim = N_CHAR_MAX // 2 # apprx number of chars to keep on both ends
|
||
|
|
regex = r'^(\s*\S){%d}' % lim
|
||
|
|
# The regex '^(\s*\S){%d}' % n
|
||
|
|
# matches from the start of the string until the nth non-blank
|
||
|
|
# character:
|
||
|
|
# - ^ matches the start of string
|
||
|
|
# - (pattern){n} matches n repetitions of pattern
|
||
|
|
# - \s*\S matches a non-blank char following zero or more blanks
|
||
|
|
left_lim = re.match(regex, repr_).end()
|
||
|
|
right_lim = re.match(regex, repr_[::-1]).end()
|
||
|
|
|
||
|
|
if '\n' in repr_[left_lim:-right_lim]:
|
||
|
|
# The left side and right side aren't on the same line.
|
||
|
|
# To avoid weird cuts, e.g.:
|
||
|
|
# categoric...ore',
|
||
|
|
# we need to start the right side with an appropriate newline
|
||
|
|
# character so that it renders properly as:
|
||
|
|
# categoric...
|
||
|
|
# handle_unknown='ignore',
|
||
|
|
# so we add [^\n]*\n which matches until the next \n
|
||
|
|
regex += r'[^\n]*\n'
|
||
|
|
right_lim = re.match(regex, repr_[::-1]).end()
|
||
|
|
|
||
|
|
ellipsis = '...'
|
||
|
|
if left_lim + len(ellipsis) < len(repr_) - right_lim:
|
||
|
|
# Only add ellipsis if it results in a shorter repr
|
||
|
|
repr_ = repr_[:left_lim] + '...' + repr_[-right_lim:]
|
||
|
|
|
||
|
|
return repr_
|
||
|
|
|
||
|
|
def __getstate__(self):
|
||
|
|
try:
|
||
|
|
state = super().__getstate__()
|
||
|
|
except AttributeError:
|
||
|
|
state = self.__dict__.copy()
|
||
|
|
|
||
|
|
if type(self).__module__.startswith('sklearn.'):
|
||
|
|
return dict(state.items(), _sklearn_version=__version__)
|
||
|
|
else:
|
||
|
|
return state
|
||
|
|
|
||
|
|
def __setstate__(self, state):
|
||
|
|
if type(self).__module__.startswith('sklearn.'):
|
||
|
|
pickle_version = state.pop("_sklearn_version", "pre-0.18")
|
||
|
|
if pickle_version != __version__:
|
||
|
|
warnings.warn(
|
||
|
|
"Trying to unpickle estimator {0} from version {1} when "
|
||
|
|
"using version {2}. This might lead to breaking code or "
|
||
|
|
"invalid results. Use at your own risk.".format(
|
||
|
|
self.__class__.__name__, pickle_version, __version__),
|
||
|
|
UserWarning)
|
||
|
|
try:
|
||
|
|
super().__setstate__(state)
|
||
|
|
except AttributeError:
|
||
|
|
self.__dict__.update(state)
|
||
|
|
|
||
|
|
def _more_tags(self):
|
||
|
|
return _DEFAULT_TAGS
|
||
|
|
|
||
|
|
def _get_tags(self):
|
||
|
|
collected_tags = {}
|
||
|
|
for base_class in reversed(inspect.getmro(self.__class__)):
|
||
|
|
if hasattr(base_class, '_more_tags'):
|
||
|
|
# need the if because mixins might not have _more_tags
|
||
|
|
# but might do redundant work in estimators
|
||
|
|
# (i.e. calling more tags on BaseEstimator multiple times)
|
||
|
|
more_tags = base_class._more_tags(self)
|
||
|
|
collected_tags.update(more_tags)
|
||
|
|
return collected_tags
|
||
|
|
|
||
|
|
|
||
|
|
class ClassifierMixin:
|
||
|
|
"""Mixin class for all classifiers in scikit-learn."""
|
||
|
|
|
||
|
|
_estimator_type = "classifier"
|
||
|
|
|
||
|
|
def score(self, X, y, sample_weight=None):
|
||
|
|
"""
|
||
|
|
Return the mean accuracy on the given test data and labels.
|
||
|
|
|
||
|
|
In multi-label classification, this is the subset accuracy
|
||
|
|
which is a harsh metric since you require for each sample that
|
||
|
|
each label set be correctly predicted.
|
||
|
|
|
||
|
|
Parameters
|
||
|
|
----------
|
||
|
|
X : array-like of shape (n_samples, n_features)
|
||
|
|
Test samples.
|
||
|
|
|
||
|
|
y : array-like of shape (n_samples,) or (n_samples, n_outputs)
|
||
|
|
True labels for X.
|
||
|
|
|
||
|
|
sample_weight : array-like of shape (n_samples,), default=None
|
||
|
|
Sample weights.
|
||
|
|
|
||
|
|
Returns
|
||
|
|
-------
|
||
|
|
score : float
|
||
|
|
Mean accuracy of self.predict(X) wrt. y.
|
||
|
|
"""
|
||
|
|
from .metrics import accuracy_score
|
||
|
|
return accuracy_score(y, self.predict(X), sample_weight=sample_weight)
|
||
|
|
|
||
|
|
|
||
|
|
class RegressorMixin:
|
||
|
|
"""Mixin class for all regression estimators in scikit-learn."""
|
||
|
|
_estimator_type = "regressor"
|
||
|
|
|
||
|
|
def score(self, X, y, sample_weight=None):
|
||
|
|
"""Return the coefficient of determination R^2 of the prediction.
|
||
|
|
|
||
|
|
The coefficient R^2 is defined as (1 - u/v), where u is the residual
|
||
|
|
sum of squares ((y_true - y_pred) ** 2).sum() and v is the total
|
||
|
|
sum of squares ((y_true - y_true.mean()) ** 2).sum().
|
||
|
|
The best possible score is 1.0 and it can be negative (because the
|
||
|
|
model can be arbitrarily worse). A constant model that always
|
||
|
|
predicts the expected value of y, disregarding the input features,
|
||
|
|
would get a R^2 score of 0.0.
|
||
|
|
|
||
|
|
Parameters
|
||
|
|
----------
|
||
|
|
X : array-like of shape (n_samples, n_features)
|
||
|
|
Test samples. For some estimators this may be a
|
||
|
|
precomputed kernel matrix or a list of generic objects instead,
|
||
|
|
shape = (n_samples, n_samples_fitted),
|
||
|
|
where n_samples_fitted is the number of
|
||
|
|
samples used in the fitting for the estimator.
|
||
|
|
|
||
|
|
y : array-like of shape (n_samples,) or (n_samples, n_outputs)
|
||
|
|
True values for X.
|
||
|
|
|
||
|
|
sample_weight : array-like of shape (n_samples,), default=None
|
||
|
|
Sample weights.
|
||
|
|
|
||
|
|
Returns
|
||
|
|
-------
|
||
|
|
score : float
|
||
|
|
R^2 of self.predict(X) wrt. y.
|
||
|
|
|
||
|
|
Notes
|
||
|
|
-----
|
||
|
|
The R2 score used when calling ``score`` on a regressor will use
|
||
|
|
``multioutput='uniform_average'`` from version 0.23 to keep consistent
|
||
|
|
with :func:`~sklearn.metrics.r2_score`. This will influence the
|
||
|
|
``score`` method of all the multioutput regressors (except for
|
||
|
|
:class:`~sklearn.multioutput.MultiOutputRegressor`). To specify the
|
||
|
|
default value manually and avoid the warning, please either call
|
||
|
|
:func:`~sklearn.metrics.r2_score` directly or make a custom scorer with
|
||
|
|
:func:`~sklearn.metrics.make_scorer` (the built-in scorer ``'r2'`` uses
|
||
|
|
``multioutput='uniform_average'``).
|
||
|
|
"""
|
||
|
|
|
||
|
|
from .metrics import r2_score
|
||
|
|
from .metrics._regression import _check_reg_targets
|
||
|
|
y_pred = self.predict(X)
|
||
|
|
# XXX: Remove the check in 0.23
|
||
|
|
y_type, _, _, _ = _check_reg_targets(y, y_pred, None)
|
||
|
|
if y_type == 'continuous-multioutput':
|
||
|
|
warnings.warn("The default value of multioutput (not exposed in "
|
||
|
|
"score method) will change from 'variance_weighted' "
|
||
|
|
"to 'uniform_average' in 0.23 to keep consistent "
|
||
|
|
"with 'metrics.r2_score'. To specify the default "
|
||
|
|
"value manually and avoid the warning, please "
|
||
|
|
"either call 'metrics.r2_score' directly or make a "
|
||
|
|
"custom scorer with 'metrics.make_scorer' (the "
|
||
|
|
"built-in scorer 'r2' uses "
|
||
|
|
"multioutput='uniform_average').", FutureWarning)
|
||
|
|
return r2_score(y, y_pred, sample_weight=sample_weight,
|
||
|
|
multioutput='variance_weighted')
|
||
|
|
|
||
|
|
|
||
|
|
class ClusterMixin:
|
||
|
|
"""Mixin class for all cluster estimators in scikit-learn."""
|
||
|
|
_estimator_type = "clusterer"
|
||
|
|
|
||
|
|
def fit_predict(self, X, y=None):
|
||
|
|
"""
|
||
|
|
Perform clustering on X and returns cluster labels.
|
||
|
|
|
||
|
|
Parameters
|
||
|
|
----------
|
||
|
|
X : ndarray, shape (n_samples, n_features)
|
||
|
|
Input data.
|
||
|
|
|
||
|
|
y : Ignored
|
||
|
|
Not used, present for API consistency by convention.
|
||
|
|
|
||
|
|
Returns
|
||
|
|
-------
|
||
|
|
labels : ndarray, shape (n_samples,)
|
||
|
|
Cluster labels.
|
||
|
|
"""
|
||
|
|
# non-optimized default implementation; override when a better
|
||
|
|
# method is possible for a given clustering algorithm
|
||
|
|
self.fit(X)
|
||
|
|
return self.labels_
|
||
|
|
|
||
|
|
|
||
|
|
class BiclusterMixin:
|
||
|
|
"""Mixin class for all bicluster estimators in scikit-learn"""
|
||
|
|
|
||
|
|
@property
|
||
|
|
def biclusters_(self):
|
||
|
|
"""Convenient way to get row and column indicators together.
|
||
|
|
|
||
|
|
Returns the ``rows_`` and ``columns_`` members.
|
||
|
|
"""
|
||
|
|
return self.rows_, self.columns_
|
||
|
|
|
||
|
|
def get_indices(self, i):
|
||
|
|
"""Row and column indices of the i'th bicluster.
|
||
|
|
|
||
|
|
Only works if ``rows_`` and ``columns_`` attributes exist.
|
||
|
|
|
||
|
|
Parameters
|
||
|
|
----------
|
||
|
|
i : int
|
||
|
|
The index of the cluster.
|
||
|
|
|
||
|
|
Returns
|
||
|
|
-------
|
||
|
|
row_ind : np.array, dtype=np.intp
|
||
|
|
Indices of rows in the dataset that belong to the bicluster.
|
||
|
|
col_ind : np.array, dtype=np.intp
|
||
|
|
Indices of columns in the dataset that belong to the bicluster.
|
||
|
|
|
||
|
|
"""
|
||
|
|
rows = self.rows_[i]
|
||
|
|
columns = self.columns_[i]
|
||
|
|
return np.nonzero(rows)[0], np.nonzero(columns)[0]
|
||
|
|
|
||
|
|
def get_shape(self, i):
|
||
|
|
"""Shape of the i'th bicluster.
|
||
|
|
|
||
|
|
Parameters
|
||
|
|
----------
|
||
|
|
i : int
|
||
|
|
The index of the cluster.
|
||
|
|
|
||
|
|
Returns
|
||
|
|
-------
|
||
|
|
shape : (int, int)
|
||
|
|
Number of rows and columns (resp.) in the bicluster.
|
||
|
|
"""
|
||
|
|
indices = self.get_indices(i)
|
||
|
|
return tuple(len(i) for i in indices)
|
||
|
|
|
||
|
|
def get_submatrix(self, i, data):
|
||
|
|
"""Return the submatrix corresponding to bicluster `i`.
|
||
|
|
|
||
|
|
Parameters
|
||
|
|
----------
|
||
|
|
i : int
|
||
|
|
The index of the cluster.
|
||
|
|
data : array
|
||
|
|
The data.
|
||
|
|
|
||
|
|
Returns
|
||
|
|
-------
|
||
|
|
submatrix : array
|
||
|
|
The submatrix corresponding to bicluster i.
|
||
|
|
|
||
|
|
Notes
|
||
|
|
-----
|
||
|
|
Works with sparse matrices. Only works if ``rows_`` and
|
||
|
|
``columns_`` attributes exist.
|
||
|
|
"""
|
||
|
|
from .utils.validation import check_array
|
||
|
|
data = check_array(data, accept_sparse='csr')
|
||
|
|
row_ind, col_ind = self.get_indices(i)
|
||
|
|
return data[row_ind[:, np.newaxis], col_ind]
|
||
|
|
|
||
|
|
|
||
|
|
class TransformerMixin:
|
||
|
|
"""Mixin class for all transformers in scikit-learn."""
|
||
|
|
|
||
|
|
def fit_transform(self, X, y=None, **fit_params):
|
||
|
|
"""
|
||
|
|
Fit to data, then transform it.
|
||
|
|
|
||
|
|
Fits transformer to X and y with optional parameters fit_params
|
||
|
|
and returns a transformed version of X.
|
||
|
|
|
||
|
|
Parameters
|
||
|
|
----------
|
||
|
|
X : numpy array of shape [n_samples, n_features]
|
||
|
|
Training set.
|
||
|
|
|
||
|
|
y : numpy array of shape [n_samples]
|
||
|
|
Target values.
|
||
|
|
|
||
|
|
**fit_params : dict
|
||
|
|
Additional fit parameters.
|
||
|
|
|
||
|
|
Returns
|
||
|
|
-------
|
||
|
|
X_new : numpy array of shape [n_samples, n_features_new]
|
||
|
|
Transformed array.
|
||
|
|
"""
|
||
|
|
# non-optimized default implementation; override when a better
|
||
|
|
# method is possible for a given clustering algorithm
|
||
|
|
if y is None:
|
||
|
|
# fit method of arity 1 (unsupervised transformation)
|
||
|
|
return self.fit(X, **fit_params).transform(X)
|
||
|
|
else:
|
||
|
|
# fit method of arity 2 (supervised transformation)
|
||
|
|
return self.fit(X, y, **fit_params).transform(X)
|
||
|
|
|
||
|
|
|
||
|
|
class DensityMixin:
|
||
|
|
"""Mixin class for all density estimators in scikit-learn."""
|
||
|
|
_estimator_type = "DensityEstimator"
|
||
|
|
|
||
|
|
def score(self, X, y=None):
|
||
|
|
"""Return the score of the model on the data X
|
||
|
|
|
||
|
|
Parameters
|
||
|
|
----------
|
||
|
|
X : array-like of shape (n_samples, n_features)
|
||
|
|
|
||
|
|
Returns
|
||
|
|
-------
|
||
|
|
score : float
|
||
|
|
"""
|
||
|
|
pass
|
||
|
|
|
||
|
|
|
||
|
|
class OutlierMixin:
|
||
|
|
"""Mixin class for all outlier detection estimators in scikit-learn."""
|
||
|
|
_estimator_type = "outlier_detector"
|
||
|
|
|
||
|
|
def fit_predict(self, X, y=None):
|
||
|
|
"""Perform fit on X and returns labels for X.
|
||
|
|
|
||
|
|
Returns -1 for outliers and 1 for inliers.
|
||
|
|
|
||
|
|
Parameters
|
||
|
|
----------
|
||
|
|
X : ndarray, shape (n_samples, n_features)
|
||
|
|
Input data.
|
||
|
|
|
||
|
|
y : Ignored
|
||
|
|
Not used, present for API consistency by convention.
|
||
|
|
|
||
|
|
Returns
|
||
|
|
-------
|
||
|
|
y : ndarray, shape (n_samples,)
|
||
|
|
1 for inliers, -1 for outliers.
|
||
|
|
"""
|
||
|
|
# override for transductive outlier detectors like LocalOulierFactor
|
||
|
|
return self.fit(X).predict(X)
|
||
|
|
|
||
|
|
|
||
|
|
class MetaEstimatorMixin:
|
||
|
|
_required_parameters = ["estimator"]
|
||
|
|
"""Mixin class for all meta estimators in scikit-learn."""
|
||
|
|
|
||
|
|
|
||
|
|
class MultiOutputMixin:
|
||
|
|
"""Mixin to mark estimators that support multioutput."""
|
||
|
|
def _more_tags(self):
|
||
|
|
return {'multioutput': True}
|
||
|
|
|
||
|
|
|
||
|
|
class _UnstableArchMixin:
|
||
|
|
"""Mark estimators that are non-determinstic on 32bit or PowerPC"""
|
||
|
|
def _more_tags(self):
|
||
|
|
return {'non_deterministic': (
|
||
|
|
_IS_32BIT or platform.machine().startswith(('ppc', 'powerpc')))}
|
||
|
|
|
||
|
|
|
||
|
|
def is_classifier(estimator):
|
||
|
|
"""Return True if the given estimator is (probably) a classifier.
|
||
|
|
|
||
|
|
Parameters
|
||
|
|
----------
|
||
|
|
estimator : object
|
||
|
|
Estimator object to test.
|
||
|
|
|
||
|
|
Returns
|
||
|
|
-------
|
||
|
|
out : bool
|
||
|
|
True if estimator is a classifier and False otherwise.
|
||
|
|
"""
|
||
|
|
return getattr(estimator, "_estimator_type", None) == "classifier"
|
||
|
|
|
||
|
|
|
||
|
|
def is_regressor(estimator):
|
||
|
|
"""Return True if the given estimator is (probably) a regressor.
|
||
|
|
|
||
|
|
Parameters
|
||
|
|
----------
|
||
|
|
estimator : object
|
||
|
|
Estimator object to test.
|
||
|
|
|
||
|
|
Returns
|
||
|
|
-------
|
||
|
|
out : bool
|
||
|
|
True if estimator is a regressor and False otherwise.
|
||
|
|
"""
|
||
|
|
return getattr(estimator, "_estimator_type", None) == "regressor"
|
||
|
|
|
||
|
|
|
||
|
|
def is_outlier_detector(estimator):
|
||
|
|
"""Return True if the given estimator is (probably) an outlier detector.
|
||
|
|
|
||
|
|
Parameters
|
||
|
|
----------
|
||
|
|
estimator : object
|
||
|
|
Estimator object to test.
|
||
|
|
|
||
|
|
Returns
|
||
|
|
-------
|
||
|
|
out : bool
|
||
|
|
True if estimator is an outlier detector and False otherwise.
|
||
|
|
"""
|
||
|
|
return getattr(estimator, "_estimator_type", None) == "outlier_detector"
|