如何按x值对含多元素的嵌套列表实现升序与降序排序？

核心思路 #

要实现按子列表中x=xx的数值排序，关键是通过key参数提取每个子列表对应的x值作为排序依据：

• 遍历子列表元素，筛选出以x=开头的字符串
• 从该字符串中提取数字部分并转为整数，作为排序的判断基准

从小到大排序代码 #

original_list = [["bla","blabla","x=17"],["bla","x=13","z=13","blabla"],["x=27","blabla","bla","y=24"]]

# 升序排序
sorted_asc = sorted(original_list, key=lambda sublist: int(next(s.split('=')[1] for s in sublist if s.startswith('x='))))
print(sorted_asc)

输出结果：

[["bla","x=13","z=13","blabla"],["bla","blabla","x=17"],["x=27","blabla","bla","y=24"]]

从大到小排序代码 #

只需在sorted()中添加reverse=True参数即可实现降序：

# 降序排序
sorted_desc = sorted(original_list, key=lambda sublist: int(next(s.split('=')[1] for s in sublist if s.startswith('x='))), reverse=True)
print(sorted_desc)

输出结果：

[["x=27","blabla","bla","y=24"],["bla","blabla","x=17"],["bla","x=13","z=13","blabla"]]

代码说明 #

• next(s.split('=')[1] for s in sublist if s.startswith('x='))：遍历子列表，定位到x=开头的字符串，分割后提取数值部分
• 转为int是为了确保按数字大小排序，而非字符串的字典序
• sorted()函数不会修改原列表，会返回新的排序后的列表

内容的提问来源于stack exchange，提问作者BlueInundation