概括 Numpy 切片 Python

Question

我不知道如何概括 numpy 数组的切片。看下面的切片：

x_train = data[:train_set_size,:-1,4:-1]    

x_valid = data[train_set_size:train_set_size+valid_set_size,:-1,4:-1]

x_test = data[train_set_size+valid_set_size:,:-1,4:-1]

y_train = data[:train_set_size,-1,-2:]

y_valid = data[train_set_size:train_set_size+valid_set_size,-1,-2:]

y_test = data[train_set_size+valid_set_size:,-1,-2:]

如您所见，xset 被切片:-1,4:-1并y设置为 -1,-2:。如果我必须进行更改，那么我需要更改 3 次，而如果有办法将切片存储在变量中，只需更改变量即可反映更改。

例如：xset_slice = ":-1,4:-1"和yset_slice = "-1,-2:"。然后只需在该位置替换为：

x_train = data[:train_set_size,xset_slice ]    

x_valid = data[train_set_size:train_set_size+valid_set_size,xset_slice ]

x_test = data[train_set_size+valid_set_size:,xset_slice ]

y_train = data[:train_set_size,-1,-2:]

y_valid = data[train_set_size:train_set_size+valid_set_size,yset_slice ]

y_test = data[train_set_size+valid_set_size:,yset_slice]

但是这种说法会出错。因此，请让我知道是否有任何类似的方法可以帮助我。

Answer 1

您可以使用 sklearn.model_selection.train_test_split X_train, X_test, y_train, y_test     = train_test_split(X, y, test_size=0.2, random_state=1) X_train, X_val, y_train, y_val     = train_test_split(X_train, y_train, test_size=0.2, random_state=1)