python - 从包含日期的列表中删除字符串，而不影响列表中的独立日期

Question

首先，对于冗长的标题感到抱歉。这是我的系统规范。 Windows 7 64 位，在 Pycharm 教育版 1.0.1 中运行 python 3.4.3 64 位

现在，进入问题。我有一个列表，其中包含从网站提取的数据。该列表包含字符串，有些只是日期，有些只是单词，有些是带单词的日期。它看起来像这样:

tempDates = ['Date', 'Visitor', 'Home', 'Notes', '2013-10-01', 'Washington Capitals', 'Chicago Blackhawks', None, '2013-10-01', 'Winnipeg Jets',..., 'St. Louis Blues',..., 'Postponed due to blizzard until 2014-02-25', etc]

我想做的是删除除独立日期之外的所有内容。使用生成器、while 循环和 if 语句，我能够删除除包含日期和单词的字符串之外的所有内容。该部分代码如下所示:

dates = []
d = 0
while d < len(tempDates):
        if tempDates[d] is None or all(i.isalpha() or i == ' ' or i == ',' or i == '-' or i == '.' for i in tempDates[d]):
            d += 1
        else:
            dates.append(tempDates[d])
            d += 1

这段代码的输出是这样的:

dates = ['2013-10-01', '2013-10-01',..., '2014-01-21', '2014-01-21', '2014-01-21', 'Postponed due to snowstorm until 2014-01-22', '2014-01-22', 'Make-up game for snowstorm 2014-01-21',..., '2014-06-13']

在不删除独立日期的情况下，我找不到任何方法来删除同时包含单词和日期的字符串。我尝试更改程序从 tempDates 中排序日期的顺序，但这只会导致更多的无限循环和内存问题。如果有帮助，这里是完整的程序:

1    from bs4 import BeautifulSoup
2    import requests
3    import pandas as pd
4    import re
5
6    # create empty lists to hold the data pulled from the website
7    dateList = []
8    gameList = []
9    winnerList = []
10    loserList = []
11
12    year = 2014 #program is made to iterate through all available seasons since 1918, but is set to start at 2014 for quicker troubleshooting
13    while year < 2016:      # stops year at 2015, as this is the last year stats are available
14        if year == 2005:    # prevents an error from the program trying to load data from 2005, as that season was canceled
15            year += 1
16        else:
17            # pulls the whole page and puts it into r
18            r = requests.get('http://www.hockey-reference.com/leagues/NHL_{}_games.html'.format(year))
19            data = r.text
20
21            soup = BeautifulSoup(data, "lxml")
22            foundTeams = soup.find_all(href=re.compile("teams"))
23            teams = [link.string for link in foundTeams]
24            teams = teams[2:]
25
26            foundScores = soup.find_all(align=re.compile("right"))
27            tempScores = [link.string for link in foundScores]
28            tempScores = tempScores[2:]
29
30            foundDates = soup.find_all(align=re.compile("left"))
31            tempDates = [link.string for link in foundDates]
32    
33            dates = []
34            d = 0
35            while d < len(tempDates):
36                if tempDates[d] is None or all(i.isalpha() or i == ' ' or i == ',' or i == '-' or i == '.' for i in tempDates[d]):
37                    d += 1
38                else:
39                    dates.append(tempDates[d])
40                    d += 1
41
42            season = soup.find('h1')
43            season = [link.string for link in season]
44
45            games = len(teams) / 2
46            games = int(games)
47
48            # goes through the pulled data and saves it into lists to be written to a compiled file
49            x = 0
50            y = 0
51            while x < len(teams):
52                if x % 2 == 0:
53                    if tempScores[x] is None or all(i.isalpha() or i == ' ' or i == ',' for i in tempScores[x]):
54                        x += 2
55                    else:
56                        print(dates[y])
57                        if tempScores[x] > tempScores[x+1]:
58                            print("In game", y + 1)
59                            print("The", teams[x], tempScores[x], "won against the", teams[x+1], tempScores[x+1])
60                            winnerList.append(teams[x])
61                            loserList.append(teams[x+1])
62                        elif tempScores[x] < tempScores[x+1]:
63                            print("In game", y + 1)
64                            print("The", teams[x+1], tempScores[x+1], "won against the", teams[x], tempScores[x])
65                            winnerList.append(teams[x+1])
66                            loserList.append(teams[x])
67                        dateList.append(dates[y])
68                        gameList.append(y)
69                        x += 1
70                        y += 1
71                else:
72                    x += 1
73            year += 1
74    
75    # converts the compiled lists to data frames
76    dateList = pd.DataFrame(dateList)
77    gameList = pd.DataFrame(gameList)
78    winnerList = pd.DataFrame(winnerList)
79    loserList = pd.DataFrame(loserList)
80    
81    # puts the data frames into one data frame
82    compiledStats = dateList
83    compiledStats['Game'] = gameList
84    compiledStats['Game Winner'] = winnerList
85    compiledStats['Game Loser'] = loserList
86    
87    # rename the columns
88    compiledStats.columns = ['Date', 'Game', 'Game Winner', 'Game Loser']
89    # write to a new file
90    compiledStats.to_csv('CSV/Compiled_NHL_Stats2.0.csv', index=False)

Answer 1

tempDates = ['Date', 'Visitor', 'Home', 'Notes', '2013-10-01', 'Washington Capitals', 'Chicago Blackhawks', None, '2013-10-01', 'Winnipeg Jets','...', 'St. Louis Blues','...', 'Postponed due to blizzard until 2014-02-25', 'etc']
print [i for i in tempDates if re.match(r"\d{4}-\d{2}-\d{2}",str(i))]

这应该为你做