将python列表切片为新的python列表

我试图将一个列表分割成三个新列表，但我的方法似乎有问题。你们能帮我看看我该怎么做吗？谢谢大家!

quiz = [[91, 94, 38, 48, 70, 85, 94, 59], [78, 96, 90, 55, 77, 82, 94, 60], [99, 94, 82, 77, 75, 89, 94, 93], [49, 92, 75, 48, 80, 95, 99, 98]]
midterm = []
final = []

我试着做一个小测验，让前五个数字排在清单的前面，期中然后是接下来的两个，最后一个数字排在清单的最后：

quiz = [[91, 94, 38, 48, 70,], [78, 96, 90, 55, 77], [99, 94, 82, 77, 75,], [49, 92, 75, 48, 80]]
midterm = [[85, 94,],[82, 94,], [89, 94,], [95, 99,]]
final = [[59], [60], [93], [98]]

这是我的代码：

quiz = [[91, 94, 38, 48, 70, 85, 94, 59], [78, 96, 90, 55, 77, 82, 94, 60], [99, 94, 82, 77, 75, 89, 94, 93], [49, 92, 75, 48, 80, 95, 99, 98]]
midterm = quiz[5:2]
final = midterm[5:1]

工作原理：

[]是for循环的压缩版本。 例如，上述代码与以下代码相同：

for i in quiz:
    midterm.append(i[5:7])
for i in quiz:
    final.append(i[7:])

tmp = []
for i in quiz:
    tmp.append(i[:5])
quiz = tmp

它几乎遍历了测验中的所有元素，取2，1和5作为单独的数组。你们做错了的是，你们并没有把测验当作二维数组，而是当作一维数组

---

您当前的代码将接受期中数组测验的第二到第五个元素，这些元素恰好是第二到第五个整数数组，而不是测验中每个数组中的第二到第五个整数。

给您：使用

列表理解

>>> quiz = [[91, 94, 38, 48, 70, 85, 94, 59], [78, 96, 90, 55, 77, 82, 94, 60], [99, 94,  82, 77, 75, 89, 94, 93], [49, 92, 75, 48, 80, 95, 99, 98]]
>>> new_quiz = [ x[:5] for x in quiz ]
>>> mid_term = [ x[5:7] for x in quiz ]
>>> final = [ x[-1:] for x in quiz ]
>>> new_quiz
[[91, 94, 38, 48, 70], [78, 96, 90, 55, 77], [99, 94, 82, 77, 75], [49, 92, 75, 48, 80]]
>>> mid_term
[[85, 94], [82, 94], [89, 94], [95, 99]]
>>> final
[[59], [60], [93], [98]]

---

你到底遇到了什么问题？

>>> quiz = [[91, 94, 38, 48, 70, 85, 94, 59], [78, 96, 90, 55, 77, 82, 94, 60], [99, 94,  82, 77, 75, 89, 94, 93], [49, 92, 75, 48, 80, 95, 99, 98]]
>>> new_quiz = [ x[:5] for x in quiz ]
>>> mid_term = [ x[5:7] for x in quiz ]
>>> final = [ x[-1:] for x in quiz ]
>>> new_quiz
[[91, 94, 38, 48, 70], [78, 96, 90, 55, 77], [99, 94, 82, 77, 75], [49, 92, 75, 48, 80]]
>>> mid_term
[[85, 94], [82, 94], [89, 94], [95, 99]]
>>> final
[[59], [60], [93], [98]]