scikits.learn.cross_val.KFold¶
- class scikits.learn.cross_val.KFold(n, k)¶
K-Folds cross validation iterator: Provides train/test indexes to split data in train test sets
- __init__(n, k)¶
K-Folds cross validation iterator: Provides train/test indexes to split data in train test sets
Parameters : n: int :
Total number of elements
k: int :
number of folds
Notes
All the folds have size trunc(n/k), the last one has the complementary
Examples
>>> from scikits.learn import cross_val >>> X = [[1, 2], [3, 4], [1, 2], [3, 4]] >>> y = [1, 2, 3, 4] >>> kf = cross_val.KFold(4, k=2) >>> len(kf) 2 >>> print kf scikits.learn.cross_val.KFold(n=4, k=2) >>> for train_index, test_index in kf: ... print "TRAIN:", train_index, "TEST:", test_index ... X_train, X_test, y_train, y_test = cross_val.split(train_index, test_index, X, y) TRAIN: [False False True True] TEST: [ True True False False] TRAIN: [ True True False False] TEST: [False False True True]