enumerate() 函数用于将一个可遍历的数据对象(如列表、元组或字符串)组合为一个索引序列,同时列出数据和数据下标,一般用在 for 循环当中。
示例代码:
#!/usr/bin/env python
x_train = [[1, 2, 3], [3, 4, 5], [5, 6, 7]]
y_train = [1, 2, 3]
db = zip(x_train, y_train)
for step, (x_train, y_train) in enumerate(db):
print(step, x_train, y_train, sep='\t')
运行结果:
0 [1, 2, 3] 1
1 [3, 4, 5] 2
2 [5, 6, 7] 3
[Finished in 0.2s]