IndexError: index 6 is out of bounds for axis 1 with size 6

오류:
Using TensorFlow backend.Traceback (most recent call last):  File "E:/Python3Doc/APIdocs/kerasMy/to-cat.py", line 7, in     y_train_use = np_utils.to_categorical(y_train, num_classes=nb_classes)  File "C:\Program Files\Anaconda3\lib\site-packages\keras\utilsp_utils.py", line 31, in to_categorical    categorical[np.arange(n), y] = 1
IndexError: index 6 is out of bounds for axis 1 with size 6

# coding: utf-8

from keras.utils import np_utils

nb_classes = 6
y_train = [1, 3, 5, 2, 6, 4, 1]
y_train_use = np_utils.to_categorical(y_train, num_classes=nb_classes)

print(y_train_use)

수정: nbclasses = 7, 즉 클래스 레이 블 은 0 부터 시작 해 야 합 니 다!!!!!!!!!!!!!
다음 과 같다.

# coding: utf-8

from keras.utils import np_utils

nb_classes = 7
y_train = [1, 3, 5, 2, 6, 4, 1]
y_train_use = np_utils.to_categorical(y_train, num_classes=nb_classes)

print(y_train_use)

결과:
[[ 0.  1.  0.  0.  0.  0.  0.] [ 0.  0.  0.  1.  0.  0.  0.] [ 0.  0.  0.  0.  0.  1.  0.] [ 0.  0.  1.  0.  0.  0.  0.] [ 0.  0.  0.  0.  0.  0.  1.] [ 0.  0.  0.  0.  1.  0.  0.] [ 0.  1.  0.  0.  0.  0.  0.]]