使用串联的数据框时，为什么会出现“ IndexError：字符串索引超出范围”

Question

所以基本上我在两种情况下使用相同的代码。

情况1：我使用csv模块打开并读取一个csv文件，并对从该csv文件获取的数据实施代码。 在这种情况下，代码可以正常工作

情况2：我使用相同的代码，但是这次而不是使用csv模块，而是使用pandas和glob来连接2个csv文件（相同的行和列数），在新连接的数据帧上实现代码，但得到错误'IndexError ：字符串索引超出范围”。

import pandas as pd
import glob

path = r’Q:\Users\Panagiotis\Betting formula\EPL Seasons’
all_files = glob.glob(path + “/*.csv”)

li = []

for filename in all_files:
df = pd.read_csv(filename, index_col=None, header=0)
li.append(df)

frame = pd.concat(li, axis=0, ignore_index=True)

upsets = 0
non_upsets = 0

starting_bankroll = 100 
wagering_size = 5

bankroll = starting_bankroll

for game in frame:
    home_team = game[2]
    away_team = game[3]

    home_goals = int(game[4])
    away_goals = int(game[5])

    home_odds = float(game[23])
    draw_odds = float(game[24])
    away_odds = float(game[25])

    if home_odds > away_odds:
        if home_goals > away_goals:
            upsets += 1
            bankroll += wagering_size * (home_odds - 1)
        else:
            non_upsets += 1
            bankroll -= wagering_size

ROI = ((bankroll - starting_bankroll) / (wagering_size * (upsets + 
non_upsets))) * 100

print (“There were ‘%s’ upsets out of ‘%s’ total matches” % (upsets, 
upsets + non_upsets))
print (“Starting bankroll = ‘%s’” % (starting_bankroll))
print (“Finishing bankroll = ‘%s’ | ROI = ‘%s’” % (bankroll, ROI))

这是完整的错误消息：

  File "<ipython-input-1-27ce3bbe0a95>", line 1, in <module>
    runfile('Q:/Users/Panagiotis/Betting formula/csv concatenation formula.py', wdir='Q:/Users/Panagiotis/Betting formula')

  File "Q:\Users\Panagiotis\Anaconda3\lib\site-packages\spyder_kernels\customize\spydercustomize.py", line 786, in runfile
    execfile(filename, namespace)

  File "Q:\Users\Panagiotis\Anaconda3\lib\site-packages\spyder_kernels\customize\spydercustomize.py", line 110, in execfile
    exec(compile(f.read(), filename, 'exec'), namespace)

  File "Q:/Users/Panagiotis/Betting formula/csv concatenation formula.py", line 27, in <module>
    away_team = game[3]

IndexError: string index out of range

这是来自print（frame）的示例：

    Div      Date        HomeTeam        AwayTeam  ...  BbAvAHA   PSCH   PSCD   PSCA
0    E0  13-08-16         Burnley         Swansea  ...     1.81   2.79   3.16   2.89
1    E0  13-08-16  Crystal Palace       West Brom  ...     1.85   2.25   3.15   3.86```

Answer 1

对于您的情况，请重新检查您的frame数据。

您可以通过print出数据来检查它：

for game in frame:
    print(game, len(game))

可以肯定的是，至少一款game内的字符数少于4个。 例如pyt ，因此当您调用game[3] ， string index out of range