我正在尝试对具有四个变量的df进行随机森林k折交叉验证，例如
df="A","A1","A2","A3"
但是我总是收到错误消息
"None of [Int64Index([ 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22,\n 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39,\n 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50],\n dtype='int64')] are in the [columns]"
如果有人可以帮助我，我将不胜感激。
代码行
from sklearn.model_selection import KFold
X=df.loc[:,["A","A1","A2","A3"]]
predictors=X[["A1","A2","A3"]]
targets = X.A
cv = model_selection.KFold(n_splits=10)
for train_index, test_index in kf.split(X):
print("TRAIN:", train_index, "TEST:", test_index)
X_train, X_test = predictors[train_index], predictors[test_index]
y_train, y_test = targets[train_index], targets[test_index]
错误：
TRAIN: [ 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29
30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50] TEST: [0 1 2 3 4 5]
---------------------------------------------------------------------------
KeyError Traceback (most recent call last)
<ipython-input-19-1341237a8f9e> in <module>
15 for train_index, test_index in kf.split(X):
16 print("TRAIN:", train_index, "TEST:", test_index)
---> 17 X_train, X_test = predictors[train_index], predictors[test_index]
18 y_train, y_test = targets[train_index], targets[test_index]
19
~\anaconda3\lib\site-packages\pandas\core\frame.py in __getitem__(self, key)
2932 key = list(key)
2933 indexer = self.loc._convert_to_indexer(key, axis=1,
-> 2934 raise_missing=True)
2935
2936 # take() does not accept boolean indexers
~\anaconda3\lib\site-packages\pandas\core\indexing.py in _convert_to_indexer(self, obj, axis, is_setter, raise_missing)
1352 kwargs = {'raise_missing': True if is_setter else
1353 raise_missing}
-> 1354 return self._get_listlike_indexer(obj, axis, **kwargs)[1]
1355 else:
1356 try:
~\anaconda3\lib\site-packages\pandas\core\indexing.py in _get_listlike_indexer(self, key, axis, raise_missing)
1159 self._validate_read_indexer(keyarr, indexer,
1160 o._get_axis_number(axis),
-> 1161 raise_missing=raise_missing)
1162 return keyarr, indexer
1163
~\anaconda3\lib\site-packages\pandas\core\indexing.py in _validate_read_indexer(self, key, indexer, axis, raise_missing)
1244 raise KeyError(
1245 u"None of [{key}] are in the [{axis}]".format(
-> 1246 key=key, axis=self.obj._get_axis_name(axis)))
1247
1248 # We (temporarily) allow for some missing keys with .loc, except in
KeyError: "None of [Int64Index([ 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22,\n 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39,\n 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50],\n dtype='int64')] are in the [columns]"