如何在没有导入的情况下二维截断 3d python 列表

Question

否 numpy

所以我这里有一个 3d 列表：

list = [
        [
            # red (5 rows x 10 columns)
            [10, 10, 10, 10, 10, 10, 10, 10, 10, 10],
            [10, 10, 10, 10, 10, 10, 10, 10, 10, 10],
            [10, 10, 10, 10, 10, 10, 10, 10, 10, 10],
            [10, 10, 10, 10, 10, 10, 10, 10, 10, 10],
            [10, 10, 10, 10, 10, 10, 10, 10, 10, 10],
        ],
        [
            # green (5 rows x 10 columns)
            [10, 10, 10, 10, 10, 10, 10, 10, 10, 10],
            [10, 10, 10, 10, 10, 10, 10, 10, 10, 10],
            [10, 10, 10, 10, 10, 10, 10, 10, 10, 10],
            [10, 10, 10, 10, 10, 10, 10, 10, 10, 10],
            [10, 10, 10, 10, 10, 10, 10, 10, 10, 10],
        ],
        [
            # blue (5 rows x 10 columns)
            [10, 10, 10, 10, 10, 10, 10, 10, 10, 10],
            [10, 10, 10, 10, 10, 10, 10, 10, 10, 10],
            [10, 10, 10, 10, 10, 10, 10, 10, 10, 10],
            [10, 10, 10, 10, 10, 10, 10, 10, 10, 10],
            [10, 10, 10, 10, 10, 10, 10, 10, 10, 10],
        ],
    ]

基本上，（行，列）中的每个索引（x，y）都是一个像素，r，g，b。 这个列表有 5x10=50 像素。 我想截断它，使列和行达到指定的数量，例如 row=3，column=7，如下所示：

list = [
        [
            # red (3 rows x 7 columns)
            [10, 10, 10, 10, 10, 10, 10],
            [10, 10, 10, 10, 10, 10, 10],
            [10, 10, 10, 10, 10, 10, 10],
        ],
        [
            # green (3 rows x 7 columns)
            [10, 10, 10, 10, 10, 10, 10],
            [10, 10, 10, 10, 10, 10, 10],
            [10, 10, 10, 10, 10, 10, 10],
        ],
        [
            # blue (3 rows x 7 columns)
            [10, 10, 10, 10, 10, 10, 10],
            [10, 10, 10, 10, 10, 10, 10],
            [10, 10, 10, 10, 10, 10, 10],
        ],
    ]

Answer 1

truncated = [[row[:7] for row in color[:3]] for color in list]

您不应该使用list作为变量名，因为您正在覆盖内置list ，这可能会导致代码中出现意外行为

Answer 2

desired_rows = 3
desired_columns = 7
for i in range(len(list)):
    list[i] = list[i][:desired_rows]  # will give a 3x10 array
    for j in (range(desired_rows)):
        list[i][j] = list[i][j][:desired_columns] # will give a 3x7 array
print(list)