Question

我有一个包含许多行和两列的2D数组。我想提取这个2D数组的所有行，其中第一列有一个匹配列表中任何子字符串的字符串。

请参阅下面的人为举例。

students_mat = [['Ant', 'Bat', 'Cat', 'Dog', 'Ear'] , [3.75, 4.32, 2.43, 3.73,  2.51]]


subset_ids = ['A', 'B', 'E']

我想要输出

 accepted_std = [['Ant', 'Bat', 'Ear'] , [3.75, 4.32, 2.51]]

我试过

accepted_std = [s for s in students_mat if any(xs in s for xs in subset_ids)]

这不起作用，但它适用于一维列表。

谢谢＆amp;问候，桑托什

Answer 1

students_mat = [['Ant', 'Bat', 'Cat', 'Dog', 'Ear'] , [3.75, 4.32, 2.43, 3.73,  2.51]]
subset_ids = ['A', 'B', 'E']

# we need corresponding pairs from first and second subarrays
pairs = zip(*students_mat)

# filtering
filtered_pairs = ((x, y) for x, y in pairs if x[0] in subset_ids)

# returning to original form
original = zip(*filtered_pairs)

# converting to list of lists
accepted_std = list(map(list, original))

Answer 2

你可以试试这个：

students_mat = [['Ant', 'Bat', 'Cat', 'Dog', 'Ear'] , [3.75, 4.32, 2.43, 3.73,  2.51]]
subset_ids = ['A', 'B', 'E']
indicies = [i for i, a in enumerate(students_mat[0]) if a[0] in subset_ids]
final_data = [[c for i, c in enumerate(a) if i in indicies] for a in students_mat]

输出：

[['Ant', 'Bat', 'Ear'], [3.75, 4.32, 2.51]]

Answer 3

您需要将两个列表转换为元组列表，然后将它们转换回两个列表：

accepted_std = zip(*
  [
    (txt, num) for (txt, num) in zip(students_mat[0], students_mat[1])
     if any(xs in txt for xs in subset_ids)
 ]
)

您可以使用zip命令从简单列表创建元组列表：

for (txt, num) in zip(students_map[0], students_map[1])

然后，您可以使用与之前相同的方法过滤txt变量：

if any(xs in txt for xs in subset_ids)

最后，您需要解压缩元组列表。 zip(*list)正好适用于此。

基于正则表达式的匹配在Python中切片2D列表

3 个答案: