python排序负数和/或十进制字母数字字符串

时间:2017-06-30 01:51:56

标签: python sorting numbers decimal alphanumeric

我在排序包含负数和/或十进制字母数字字符串的字符串列表时遇到问题。这就是我到目前为止所做的:

import re

format_ids = ["synopsys_SS_2v_-40c_SS.lib",
              "synopsys_SS_1v_-40c_SS.lib",
              "synopsys_SS_1.2v_-40c_SS.lib", 
              "synopsys_SS_1.4v_-40c_SS.lib",
              "synopsys_SS_2v_-40c_TT.lib",
              "synopsys_FF_3v_25c_FF.lib",
              "synopsys_TT_4v_125c_TT.lib",
              "synopsys_TT_1v_85c_TT.lib",
              "synopsys_TT_10v_85c_TT.lib",
              "synopsys_FF_3v_-40c_SS.lib",
              "synopsys_FF_3v_-40c_TT.lib"]

selector = r'.*(FF|TT|SS)_([-\.\d]+v)_([-\.\d]+c)_(FF|TT|SS).*'
#key = [2,1,3]
key = 2
produce_groups = False

if isinstance(key, int):
    key = [key]

convert = lambda text: float(text) if text.isdigit() else text
alphanum_key = lambda k: [convert(c) for c in re.split('([-.\d]+)', k)]
split_list = lambda name: tuple(alphanum_key(re.findall(selector,name)[0][i]) for i in key)
format_ids.sort(key=split_list)

print "\n".join(format_ids)

我期待以下输出(按第3个键排序):

synopsys_SS_2v_-40c_SS.lib
synopsys_SS_1v_-40c_SS.lib
synopsys_SS_1.2v_-40c_SS.lib
synopsys_SS_1.4v_-40c_SS.lib
synopsys_SS_2v_-40c_TT.lib
synopsys_FF_3v_-40c_SS.lib
synopsys_FF_3v_-40c_TT.lib
synopsys_FF_3v_25c_FF.lib
synopsys_TT_1v_85c_TT.lib
synopsys_TT_10v_85c_TT.lib
synopsys_TT_4v_125c_TT.lib

但我得到以下内容(所有负数都列在最后):

synopsys_FF_3v_25c_FF.lib
synopsys_TT_1v_85c_TT.lib
synopsys_TT_10v_85c_TT.lib
synopsys_TT_4v_125c_TT.lib
synopsys_SS_2v_-40c_SS.lib
synopsys_SS_1v_-40c_SS.lib
synopsys_SS_1.2v_-40c_SS.lib
synopsys_SS_1.4v_-40c_SS.lib
synopsys_SS_2v_-40c_TT.lib
synopsys_FF_3v_-40c_SS.lib
synopsys_FF_3v_-40c_TT.lib

现在,对于第二个键的小数(将键变量更改为1(键= 1)),我得到:

synopsys_SS_1v_-40c_SS.lib
synopsys_TT_1v_85c_TT.lib
synopsys_SS_2v_-40c_SS.lib
synopsys_SS_2v_-40c_TT.lib
synopsys_FF_3v_25c_FF.lib
synopsys_FF_3v_-40c_SS.lib
synopsys_FF_3v_-40c_TT.lib
synopsys_TT_4v_125c_TT.lib
synopsys_TT_10v_85c_TT.lib
synopsys_SS_1.2v_-40c_SS.lib
synopsys_SS_1.4v_-40c_SS.lib

期待:

synopsys_SS_1v_-40c_SS.lib
synopsys_TT_1v_85c_TT.lib
synopsys_SS_1.2v_-40c_SS.lib
synopsys_SS_1.4v_-40c_SS.lib
synopsys_SS_2v_-40c_SS.lib
synopsys_SS_2v_-40c_TT.lib
synopsys_FF_3v_25c_FF.lib
synopsys_FF_3v_-40c_SS.lib
synopsys_FF_3v_-40c_TT.lib
synopsys_TT_4v_125c_TT.lib
synopsys_TT_10v_85c_TT.lib

非常感谢任何建议。

编辑:我最终使用@StephenRauch描述的simpler method

import re
def sort_names(format_ids, selector, key=1):

    if isinstance(key, int):
        key = [key]

    SELECTOR_RE = re.compile(selector)

    def convert(x):
        try:
            return float(x[:-1])
        except ValueError:
            return x

    def sort_keys(key):
        def split_fid(x):
            x = SELECTOR_RE.split(x)
            return tuple([convert(x[i]) for i in key])
        return split_fid

    format_ids.sort(key=sort_keys(key))

format_ids = ["synopsys_SS_2v_-40c_SS.lib",
              "synopsys_SS_1v_-40c_SS.lib",
              "synopsys_SS_1.2v_-40c_SS.lib",
              "synopsys_SS_1.4v_-40c_SS.lib",
              "synopsys_SS_2v_-40c_TT.lib",
              "synopsys_FF_3v_25c_FF.lib",
              "synopsys_TT_4v_125c_TT.lib",
              "synopsys_TT_1v_85c_TT.lib",
              "synopsys_TT_10v_85c_TT.lib",
              "synopsys_FF_3v_-40c_SS.lib",
              "synopsys_FF_3v_-40c_TT.lib"]

selector = r'.*(FF|TT|SS)_([-\.\d]+v)_([-\.\d]+c)_(FF|TT|SS).*'
key = [2,1,3]

sort_names(format_ids,selector,key)

2 个答案:

答案 0 :(得分:1)

你的问题的很大一部分是只有实际数字被认为是数字,而不是破折号和句号,所以在你的代码中,诸如“-40”.isdigit()或“1.4”.isdigit()之类的东西将是False,并且保留为文本而不是转换为浮点数。

答案 1 :(得分:1)

需要对数字进行一些不同的测试,并且re.split()被赋予一个领先的'',它正在抛弃转换例程。

固定代码:

key = [2,1,3]

def convert(x):
    try:
        return float(x)
    except ValueError:
        return x

alphanum_keys = lambda k: (convert(c) for c in re.split('([-.\d]+)', k))
alphanum_key = lambda k: [i for i in alphanum_keys(k) if i != ''][0]
split_list = lambda name: [
    alphanum_key(re.findall(selector, name)[0][i]) for i in key]
format_ids.sort(key=split_list)

替代(更简单)的解决方案:

但是......所有这些lambdas和regexs都比你需​​要的问题复杂得多。怎么样:

def sort_key(keys):

    def convert(x):
        try:
            return float(x[:-1])
        except ValueError:
            return x

    def f(x):
        x = x.split('_')
        return tuple([convert(x[i]) for i in keys])
    return f

format_ids.sort(key=sort_key([3, 2, 4]))

如何?

sort_keys()会返回一个函数f()。这是传递给sort()以评估排序顺序的一个参数的函数。函数f()将使用传递给sort_keys()的键的值,因为它们是值available at the time f() is defined。这称为closure

结果:

synopsys_SS_1v_-40c_SS.lib
synopsys_SS_1.2v_-40c_SS.lib
synopsys_SS_1.4v_-40c_SS.lib
synopsys_SS_2v_-40c_SS.lib
synopsys_SS_2v_-40c_TT.lib
synopsys_FF_3v_-40c_SS.lib
synopsys_FF_3v_-40c_TT.lib
synopsys_FF_3v_25c_FF.lib
synopsys_TT_1v_85c_TT.lib
synopsys_TT_10v_85c_TT.lib
synopsys_TT_4v_125c_TT.lib