问题
I am using ShuffleSplit to shuffle data, but I found there is an error
TypeError Traceback (most recent call last)
<ipython-input-36-192f7c286a58> in <module>()
1 # Fit the training data to the model using grid search
----> 2 reg = fit_model(X_train, y_train)
3
4 # Produce the value for 'max_depth'
5 print "Parameter 'max_depth' is {} for the optimal model.".format(reg.get_params()['max_depth'])
<ipython-input-34-18b2799e585c> in fit_model(X, y)
32
33 # Fit the grid search object to the data to compute the optimal model
---> 34 grid = grid.fit(X, y)
35
36 # Return the optimal model after fitting the data
/Library/Python/2.7/site-packages/sklearn/grid_search.pyc in fit(self, X, y)
827
828 """
--> 829 return self._fit(X, y, ParameterGrid(self.param_grid))
830
831
/Library/Python/2.7/site-packages/sklearn/grid_search.pyc in _fit(self, X, y, parameter_iterable)
571 self.fit_params, return_parameters=True,
572 error_score=self.error_score)
--> 573 for parameters in parameter_iterable
574 for train, test in cv)
575
/Library/Python/2.7/site-packages/sklearn/externals/joblib/parallel.pyc in __call__(self, iterable)
756 # was dispatched. In particular this covers the edge
757 # case of Parallel used with an exhausted iterator.
--> 758 while self.dispatch_one_batch(iterator):
759 self._iterating = True
760 else:
/Library/Python/2.7/site-packages/sklearn/externals/joblib/parallel.pyc in dispatch_one_batch(self, iterator)
601
602 with self._lock:
--> 603 tasks = BatchedCalls(itertools.islice(iterator, batch_size))
604 if len(tasks) == 0:
605 # No more tasks available in the iterator: tell caller to stop.
/Library/Python/2.7/site-packages/sklearn/externals/joblib/parallel.pyc in __init__(self, iterator_slice)
125
126 def __init__(self, iterator_slice):
--> 127 self.items = list(iterator_slice)
128 self._size = len(self.items)
129
/Library/Python/2.7/site-packages/sklearn/grid_search.pyc in <genexpr>((parameters,))
572 error_score=self.error_score)
573 for parameters in parameter_iterable
--> 574 for train, test in cv)
575
576 # Out is a list of triplet: score, estimator, n_test_samples
TypeError: 'ShuffleSplit' object is not iterable
And it showed the warning
/Library/Python/2.7/site-packages/sklearn/cross_validation.py:44: DeprecationWarning: This module was deprecated in version 0.18 in favor of the model_selection module into which all the refactored classes and functions are moved. Also note that the interface of the new CV iterators are different from that of this module. This module will be removed in 0.20. "This module will be removed in 0.20.", DeprecationWarning) /Library/Python/2.7/site-packages/sklearn/grid_search.py:43: DeprecationWarning: This module was deprecated in version 0.18 in favor of the model_selection module into which all the refactored classes and functions are moved. This module will be removed in 0.20. DeprecationWarning)
The code will cause the error
from sklearn.metrics import make_scorer
from sklearn.tree import DecisionTreeRegressor
from sklearn.grid_search import GridSearchCV
while the following not
from sklearn.model_selection import GridSearchCV
from sklearn.tree import DecisionTreeRegressor
from sklearn.metrics import make_scorer
The current scikit-learn version is 0.18.1.
How does this happen?
回答1:
While importing GridSearchCV from grid_search like this:
from sklearn.grid_search import GridSearchCV
You must get a warning like the following:
This module was deprecated in version 0.18 in favor of the model_selection module into which all the refactored classes and functions are moved. Also note that the interface of the new CV iterators are different from that of this module. This module will be removed in 0.20.
This is self explanatory and conforms to what you are experiencing.
Solution:-
Dont use the deprecated grid_search package. Use the new model_selection.
来源：https://stackoverflow.com/questions/43176916/typeerror-shufflesplit-object-is-not-iterable