def _fit_and_score(estimator,
X,
y,
scorer,
train,
test,
verbose,
parameters,
fit_params,
return_train_score=False,
return_parameters=False,
return_n_test_samples=False,
return_times=False,
error_score='raise'):
"""Fit estimator and compute scores for a given dataset split.
Parameters
----------
estimator : estimator object implementing 'fit'
The object to use to fit the data.
X : array-like of shape at least 2D
The data to fit.
y : array-like, optional, default: None
The target variable to try to predict in the case of
supervised learning.
scorer : A single callable or dict mapping scorer name to the callable
If it is a single callable, the return value for ``train_scores`` and
``test_scores`` is a single float.
For a dict, it should be one mapping the scorer name to the scorer
callable object / function.
The callable object / fn should have signature
``scorer(estimator, X, y)``.
train : array-like, shape (n_train_samples,)
Indices of training samples.
test : array-like, shape (n_test_samples,)
Indices of test samples.
verbose : integer
The verbosity level.
error_score : 'raise' (default) or numeric
Value to assign to the score if an error occurs in estimator fitting.
If set to 'raise', the error is raised. If a numeric value is given,
FitFailedWarning is raised. This parameter does not affect the refit
step, which will always raise the error.
parameters : dict or None
Parameters to be set on the estimator.
fit_params : dict or None
Parameters that will be passed to ``estimator.fit``.
return_train_score : boolean, optional, default: False
Compute and return score on training set.
return_parameters : boolean, optional, default: False
Return parameters that has been used for the estimator.
return_n_test_samples : boolean, optional, default: False
Whether to return the ``n_test_samples``
return_times : boolean, optional, default: False
Whether to return the fit/score times.
Returns
-------
train_scores : dict of scorer name -> float, optional
Score on training set (for all the scorers),
returned only if `return_train_score` is `True`.
test_scores : dict of scorer name -> float, optional
Score on testing set (for all the scorers).
n_test_samples : int
Number of test samples.
fit_time : float
Time spent for fitting in seconds.
score_time : float
Time spent for scoring in seconds.
parameters : dict or None, optional
The parameters that have been evaluated.
"""
if verbose > 1:
if parameters is None:
msg = ''
else:
msg = '%s' % (', '.join('%s=%s' % (k, v)
for k, v in parameters.items()))
print("[CV] %s %s" % (msg, (64 - len(msg)) * '.'))
# Adjust length of sample weights
fit_params = fit_params if fit_params is not None else {}
fit_params = dict([(k, _index_param_value(X, v, train))
for k, v in fit_params.items()])
if "indices" in inspect.signature(estimator.fit).parameters:
fit_params["indices"] = train # the different part
test_scores = {}
train_scores = {}
if parameters is not None:
estimator.set_params(**parameters)
start_time = time.time()
X_train, y_train = _safe_split(estimator, X, y, train)
X_test, y_test = _safe_split(estimator, X, y, test, train)
is_multimetric = not callable(scorer)
n_scorers = len(scorer.keys()) if is_multimetric else 1
try:
if y_train is None:
estimator.fit(X_train, **fit_params)
else:
estimator.fit(X_train, y_train, **fit_params)
except Exception as e:
# Note fit time as time until error
fit_time = time.time() - start_time
score_time = 0.0
if error_score == 'raise':
raise
elif isinstance(error_score, numbers.Number):
if is_multimetric:
test_scores = dict(
zip(scorer.keys(), [
error_score,
] * n_scorers))
if return_train_score:
train_scores = dict(
zip(scorer.keys(), [
error_score,
] * n_scorers))
else:
test_scores = error_score
if return_train_score:
train_scores = error_score
warnings.warn(
"Classifier fit failed. The score on this train-test"
" partition for these parameters will be set to %f. "
"Details: \n%r" % (error_score, e), FitFailedWarning)
else:
raise ValueError("error_score must be the string 'raise' or a"
" numeric value. (Hint: if using 'raise', please"
" make sure that it has been spelled correctly.)")
else:
fit_time = time.time() - start_time
# _score will return dict if is_multimetric is True
test_scores = _score(estimator, X_test, y_test, scorer, is_multimetric)
score_time = time.time() - start_time - fit_time
if return_train_score:
train_scores = _score(estimator, X_train, y_train, scorer,
is_multimetric)
if verbose > 2:
if is_multimetric:
for scorer_name, score in test_scores.items():
msg += ", %s=%s" % (scorer_name, score)
else:
msg += ", score=%s" % test_scores
if verbose > 1:
total_time = score_time + fit_time
end_msg = "%s, total=%s" % (msg, logger.short_format_time(total_time))
print("[CV] %s %s" % ((64 - len(end_msg)) * '.', end_msg))
ret = [train_scores, test_scores] if return_train_score else [test_scores]
if return_n_test_samples:
ret.append(_num_samples(X_test))
if return_times:
ret.extend([fit_time, score_time])
if return_parameters:
ret.append(parameters)
return ret
def _model_fit_and_score(estimator_str,
X,
y,
scorer,
train,
test,
verbose,
parameters,
fit_params,
return_train_score=False,
return_parameters=False,
return_n_test_samples=False,
return_times=False,
error_score='raise'):
"""
"""
if verbose > 1:
msg = '[CV model=%s]' % estimator_str.upper()
if parameters is not None:
msg += ' %s' % (', '.join('%s=%s' % (k, v)
for k, v in parameters.items()))
LOG.info("%s %s", msg, (89 - len(msg)) * '.')
estimator = _clf_build(estimator_str)
# Adjust length of sample weights
fit_params = fit_params if fit_params is not None else {}
fit_params = dict([(k, _index_param_value(X, v, train))
for k, v in fit_params.items()])
if parameters is not None:
estimator.set_params(**parameters)
start_time = time.time()
X_train, y_train = _safe_split(estimator, X, y, train)
X_test, y_test = _safe_split(estimator, X, y, test, train)
try:
if y_train is None:
estimator.fit(X_train, **fit_params)
else:
estimator.fit(X_train, y_train, **fit_params)
except Exception as e:
# Note fit time as time until error
fit_time = time.time() - start_time
score_time = 0.0
if error_score == 'raise':
raise
elif isinstance(error_score, numbers.Number):
test_score = error_score
if return_train_score:
train_score = error_score
warnings.warn(
"Classifier fit failed. The score on this train-test"
" partition for these parameters will be set to %f. "
"Details: \n%r" % (error_score, e), FitFailedWarning)
else:
raise ValueError("error_score must be the string 'raise' or a"
" numeric value. (Hint: if using 'raise', please"
" make sure that it has been spelled correctly.)")
else:
fit_time = time.time() - start_time
scorer = check_scoring(estimator, scoring=scorer)
test_score = _score(estimator, X_test, y_test, scorer)
score_time = time.time() - start_time - fit_time
if return_train_score:
train_score = _score(estimator, X_train, y_train, scorer)
if verbose > 2:
msg += ", score=%f" % test_score
if verbose > 1:
total_time = score_time + fit_time
end_msg = "%s, total=%s" % (msg, logger.short_format_time(total_time))
LOG.info(end_msg)
ret = [train_score, test_score] if return_train_score else [test_score]
if return_n_test_samples:
ret.append(_num_samples(X_test))
if return_times:
ret.extend([fit_time, score_time])
if return_parameters:
ret.append((estimator_str, parameters))
return ret
def _model_fit_and_score(estimator_str, X, y, scorer, train, test, verbose,
parameters, fit_params, return_train_score=False,
return_parameters=False, return_n_test_samples=False,
return_times=False, error_score='raise'):
"""
"""
if verbose > 1:
msg = '[CV model=%s]' % estimator_str.upper()
if parameters is not None:
msg += ' %s' % (', '.join('%s=%s' % (k, v)
for k, v in parameters.items()))
LOG.info("%s %s", msg, (89 - len(msg)) * '.')
estimator = _clf_build(estimator_str)
# Adjust length of sample weights
fit_params = fit_params if fit_params is not None else {}
fit_params = dict([(k, _index_param_value(X, v, train))
for k, v in fit_params.items()])
if parameters is not None:
estimator.set_params(**parameters)
start_time = time.time()
X_train, y_train = _safe_split(estimator, X, y, train)
X_test, y_test = _safe_split(estimator, X, y, test, train)
try:
if y_train is None:
estimator.fit(X_train, **fit_params)
else:
estimator.fit(X_train, y_train, **fit_params)
except Exception as e:
# Note fit time as time until error
fit_time = time.time() - start_time
score_time = 0.0
if error_score == 'raise':
raise
elif isinstance(error_score, numbers.Number):
test_score = error_score
if return_train_score:
train_score = error_score
warnings.warn("Classifier fit failed. The score on this train-test"
" partition for these parameters will be set to %f. "
"Details: \n%r" % (error_score, e), FitFailedWarning)
else:
raise ValueError("error_score must be the string 'raise' or a"
" numeric value. (Hint: if using 'raise', please"
" make sure that it has been spelled correctly.)")
else:
fit_time = time.time() - start_time
scorer = check_scoring(estimator, scoring=scorer)
test_score = _score(estimator, X_test, y_test, scorer)
score_time = time.time() - start_time - fit_time
if return_train_score:
train_score = _score(estimator, X_train, y_train, scorer)
if verbose > 2:
msg += ", score=%f" % test_score
if verbose > 1:
total_time = score_time + fit_time
end_msg = "%s, total=%s" % (msg, logger.short_format_time(total_time))
LOG.info(end_msg)
ret = [train_score, test_score] if return_train_score else [test_score]
if return_n_test_samples:
ret.append(_num_samples(X_test))
if return_times:
ret.extend([fit_time, score_time])
if return_parameters:
ret.append((estimator_str, parameters))
return ret