使用 Python 抓取网页时如何删除 pandas 数据框中的字符?

How to remove characters in pandas data frame when web scraping with Python?

我正在尝试通过使用 Python 3 将本网站的 table 内容抓取到 .csv 文件中: 2011-2012 NBA National Schedule

table 开头是这样的:

                Revised Schedule                    Original Schedule

Date            Time      Game                Net   Time      Game                  Net
Sun., 12/25/11  12 PM     BOS (1) at NY (1)   TNT   12 PM     BOS (7) at NY (7)     ESPN
Sun., 12/25/11  2:30 PM   MIA (1) at DAL (1)  ABC   2:30 PM   MIA (8) at DAL (5)    ABC
Sun., 12/25/11  5 PM      CHI (1) at LAL (1)  ABC   5 PM      CHI (6) at LAL (9)    ABC
Sun., 12/25/11  8 PM      ORL (1) at OKC (1)  ESPN  no game   no game               no game
Sun., 12/25/11  10:30 PM  LAC (1) at GS (1)   ESPN  no game   no game               no game
Tue., 12/27/11  8 PM      BOS (2) at MIA (2)  TNT   no game   no game               no game
Tue., 12/27/11  10:30 PM  UTA (1) at LAL (2)  TNT   no game   no game               no game

我只对修订后的时间表感兴趣,即前 4 列。我想要的 .csv 文件中的输出如下所示:

我正在使用这些软件包:

import re
import requests
import pandas as pd
import numpy as np
from bs4 import BeautifulSoup
from itertools import groupby

这是我为匹配我想要的格式而做的代码:

df = pd.read_html("https://www.sportsmediawatch.com/2011/12/revised-2011-12-nba-national-tv-schedule/", header=0)[0]

revisedCols = ['Date'] + [ col for col in df.columns if 'Revised' in col ]
df = df[revisedCols]

df.columns = df.iloc[0,:]

df = df.iloc[1:,:].reset_index(drop=True)


# Format Date to m/d/y
df['Date'] = np.where(df.Date.str.startswith(('10/', '11/', '12/')), df.Date + ' 11', df.Date + ' 12')
df['Date']=pd.to_datetime(df['Date'])
df['Date']=df['Date'].dt.strftime('%m/%d/%Y')

# Split the Game column
df[['Away','Home']] = df.Game.str.split('at',expand=True)   


# Final dataframe with desired columns
df = df[['Date','Time','Away','Home','Net']]

df.columns = ['Date', 'Time', 'Away', 'Home', 'Network']

print(df)

输出:

           Date      Time      Away        Home Network
0    12/25/2011     12 PM   BOS (1)      NY (1)     TNT
1    12/25/2011   2:30 PM   MIA (1)     DAL (1)     ABC
2    12/25/2011      5 PM   CHI (1)     LAL (1)     ABC
3    12/25/2011      8 PM   ORL (1)     OKC (1)    ESPN
4    12/25/2011  10:30 PM   LAC (1)      GS (1)    ESPN
5    12/27/2011      8 PM   BOS (2)     MIA (2)     TNT
6    12/27/2011  10:30 PM   UTA (1)     LAL (2)     TNT

我注意到“客场”和“主场”栏中每个球队名称旁边都有 (1)、(2) 等。 我如何实施抓取工具以删除“客场”和“主场”列中每个球队名称旁边的 (1)、(2) 等?

你可以使用str.replace with the parenthesis and the number(s) and also str.strip,因为开头或结尾似乎有一些空格:

df['Away'] = df['Away'].str.replace('\(\d*\)', '').str.strip()
df['Home'] = df['Home'].str.replace('\(\d*\)', '').str.strip()
print (df.head())
         Date      Time Away Home Network
0  12/25/2011     12 PM  BOS   NY     TNT
1  12/25/2011   2:30 PM  MIA  DAL     ABC
2  12/25/2011      5 PM  CHI  LAL     ABC
3  12/25/2011      8 PM  ORL  OKC    ESPN
4  12/25/2011  10:30 PM  LAC   GS    ESPN
import re
import numpy as np
import pandas as pd

dataset = pd.read_csv("Dataset.csv")
dataset.rename(columns={'Country(or dependent territory)': 'Country'}, inplace = True)
dataset.rename(columns={'% of worldpopulation': 'Percentage of World Population'}, inplace = True)
dataset.rename(columns={'Total Area': 'Total Area (km2)'}, inplace = True)

您可以在拆分游戏列后添加此代码

df['Away']=df['Away'].astype(str).str[0:-4]
df['Home']=df['Home'].astype(str).str[0:-4]

不要在 'at' 处拆分游戏列,不要特别声明分隔符。 .split() 将在每个白色 space 处拆分,然后您只需要 0 索引和 3rd 索引值。所以实际上只需更改 1 行代码:

来自 df[['Away','Home']] = df.Game.str.split('at',expand=True)df[['Away','Home']] = df.Game.str.split(expand=True)[[0,3]]

import pandas as pd
import numpy as np

df = pd.read_html("https://www.sportsmediawatch.com/2011/12/revised-2011-12-nba-national-tv-schedule/", header=0)[0]

revisedCols = ['Date'] + [ col for col in df.columns if 'Revised' in col ]
df = df[revisedCols]

df.columns = df.iloc[0,:]

df = df.iloc[1:,:].reset_index(drop=True)


# Format Date to m/d/y
df['Date'] = np.where(df.Date.str.startswith(('10/', '11/', '12/')), df.Date + ' 11', df.Date + ' 12')
df['Date']=pd.to_datetime(df['Date'])
df['Date']=df['Date'].dt.strftime('%m/%d/%Y')

# Split the Game column
df[['Away','Home']] = df.Game.str.split(expand=True)[[0,3]]   


# Final dataframe with desired columns
df = df[['Date','Time','Away','Home','Net']]

df.columns = ['Date', 'Time', 'Away', 'Home', 'Network']

print(df)