Error with beautiful soup: list index out of range - python

I'm a **very new programmer to python. Working on a webcrawler using urllib and beautifulsoup. Please ignore the while loop at the top and incrementation of i, I'm just running this test version, and for one page, but it will eventually include a whole set. My problem is that this gets the soup, but generates an error. I'm not sure that I'm collecting the table data correctly, but I hope that this code can ignore the links and just write the text to a .csv file. For now I'm focused on just printing the text to the screen correctly.
line 17, in <module>
uspc = col[0].string
IndexError: list index out of range
HERE is the code:
import urllib
from bs4 import BeautifulSoup
i=125
while i==125:
url = "http://www.uspto.gov/web/patents/classification/cpc/html/us" + str(i) + "tocpc.html"
print url + '\n'
i += 1
data = urllib.urlopen(url).read()
print data
#get the table data from dump
#append to csv file
soup = BeautifulSoup(data)
table = soup.find("table", width='80%')
for row in table.findAll('tr')[1:]:
col = row.findAll('td')
uspc = col[0].string
cpc1 = col[1].string
cpc2 = col[2].string
cpc3 = col[3].string
record = (uspc, cpc1, cpc2, cpc3)
print "|".join(record)

In the end, I solved this problem by changing the following line:
for row in table.findAll('tr')[1:]:
to:
for row in table.findAll('tr')[2:]:
the error was because the first row of the table had split columns

Related

How to extract specific table data (div\tr\td) from multiple URLs in a website in a literate way into CSV (with sample)

I am learning python and practicing it for extracting data in a public site.
but I found a problem in this learning. I'd like to get your kindly help me out.
Thanks for your help in advance! I will keep track this thread daily to wait for your kindly comments :)
Purpose:
extract all 65 pages' col, row with contents into a csv in one script
65 pages URLs loop rule:
http://fcjyw.dlhitech.gov.cn/ysxkzList.xhtml?method=doQuery&selYsxk=xmmc&txtkey=&pageNo=1
..........
http://fcjyw.dlhitech.gov.cn/ysxkzList.xhtml?method=doQuery&selYsxk=xmmc&txtkey=&pageNo=65
Question1:
When running below one page script to extract one page data into csv. I had to run twice with different filename, then data can be extracted to 1st time run file
for example if I run it with test.csv, excel keep 0kb status, after I change filename to test2, then run this script again, after that data can be extract to test.csv..., but test2.csv keep no data with 0 KB. any idea?
here is one page extract code:
import requests
import csv
from bs4 import BeautifulSoup as bs
url = requests.get("http://fcjyw.dlhitech.gov.cn/ysxkzList.xhtml?method=doQuery&selYsxk=xmmc&txtkey=&pageNo=1")
soup = bs(url.content, 'html.parser')
filename = "test.csv"
csv_writer = csv.writer(open(filename, 'w', newline=''))
divs = soup.find_all("div", class_ = "iiright")
for div in divs:
for tr in div.find_all("tr")[1:]:
data = []
for td in tr.find_all("td"):
data.append(td.text.strip())
if data:
print("Inserting data: {}".format(','.join(data)))
csv_writer.writerow(data)
Question2:
I found problem to literate 65 pages urls to extract data into csv.
it doesn't work... any idea fix it..
here are 65 pages urls' extract code:
import requests
import csv
from bs4 import BeautifulSoup as bs
url = "http://fcjyw.dlhitech.gov.cn/ysxkzList.xhtml?method=doQuery&selYsxk=xmmc&txtkey=&pageNo={}"
def get_data(url):
for url in [url.format(pageNo) for pageNo in range(1,65)]:
soup = bs(url.content, 'html.parser')
for div in soup.find_all("div", class_ = "iiright"):
for tr in div.find_all("tr"):
data = []
for td in tr.find_all("td"):
data.append(td.text.strip())
if data:
print("Inserting data: {}".format(','.join(data)))
writer.writerow(data)
if __name__ == '__main__':
with open("test.csv","w",newline="") as infile:
writer = csv.writer(infile)
get_data(url)
Just an alternativ approach
Try to keep it simple and may use pandas, cause it will do all these things for you under the hood.
define a list (data) to keep your results
iterate over the urls with pd.read_html
concat the data frames in data and write them to_csvor to_excel
read_html
find the table that matches a string -> match='预售信息查询:' and select it with [0] cause read_html() will always give you a list of tables
take a special row as header header =2
get rid of the last row with navigation and last column that is caused by the wrong colspan with .iloc[:-1,:-1]
Example
import pandas as pd
data = []
for pageNo in range(1,5):
data.append(pd.read_html(f'http://fcjyw.dlhitech.gov.cn/ysxkzList.xhtml?method=doQuery&selYsxk=xmmc&txtkey=&pageNo={pageNo}', header =2, match='预售信息查询:')[0].iloc[:-1,:-1])
pd.concat(data).to_csv('test.csv', index=False)
Example (based on your code with function)
import pandas as pd
url = "http://fcjyw.dlhitech.gov.cn/ysxkzList.xhtml?method=doQuery&selYsxk=xmmc&txtkey="
def get_data(url):
data = []
for pageNo in range(1,2):
data.append(pd.read_html(f'{url}&pageNo={pageNo}', header=2, match='预售信息查询:')[0].iloc[:-1,:-1])
pd.concat(data).to_csv('test.csv', index=False)
if __name__ == '__main__':
get_data(url)

Beautiful soup: processing cell data using Python

I am using python 2.7 with beautifulsoup to read in a simple HTML table.
After reading in the table, I then try to access the returned data.
As far as I can see, a python list object is returned. But when I try to access the data using statements such as cell=row[0] I get an "IndexError: list index out of range" error.
from bs4 import BeautifulSoup
# read in HTML data
html = open("in.html").read()
soup = BeautifulSoup(html,"lxml")
table = soup.find("table")
output_rows = []
for table_row in table.findAll('tr'):
columns = table_row.findAll('td')
output_row = []
for column in columns:
output_row.append(column.text)
output_rows.append(output_row)
# process some cell data
for row in output_rows:
name=row[0]
print name
# fails with list index out of range error```
I have come up with this code, to parse each cell of a row into a variable, where I can then process further. But it's not very elegant...ideas for a more elegant solution, suitable for newbies, are welcomed.
for x in range(len(row)):
if x==0:
name=row[x]
print name
if x==1:
address=row[x]
print address

Loop through a python dataframe with 10 urls and extract contents from them (BeautifulSoup)

I have a csv called 'df' with 1 column. I have a header and 10 urls.
Col
"http://www.cnn.com"
"http://www.fark.com"
etc
etc
This is my ERROR code
import bs4 as bs
df_link = pd.read_csv('df.csv')
for link in df_link:
x = urllib2.urlopen(link[0])
new = x.read()
# Code does not even get past here as far as I checked
soup = bs.BeautifulSoup(new,"lxml")
for text in soup.find_all('a',href = True):
text.append((text.get('href')))
I am getting an error which says
ValueError: unknown url type: C
I also get other variations of this error like
The issue is, it is not even getting past
x = urllib2.urlopen(link[0])
On the other hand; This is the WORKING CODE...
url = "http://www.cnn.com"
x = urllib2.urlopen(url)
new = x.read()
soup = bs.BeautifulSoup(new,"lxml")
for link in soup.find_all('a',href = True):
links.append((link.get('href')))
Fixed answer
I didn't realize you were using pandas, so what I said wasn't very helpful.
The way you want to do this using pandas is to iterate over the rows and extract the info from them. The following should work without having to get rid of the header:
import bs4 as bs
import pandas as pd
import urllib2
df_link = pd.read_csv('df.csv')
for link in df_link.iterrows():
url = link[1]['Col']
x = urllib2.urlopen(url)
new = x.read()
# Code does not even get past here as far as I checked
soup = bs.BeautifulSoup(new,"lxml")
for text in soup.find_all('a',href = True):
text.append((text.get('href')))
Original misleading answer below
It looks like the header of your CSV file is not being treated separately, and so in the first iteration through df_link, link[0] is "Col", which isn't a valid URL.

Forgetting something - Python BeautifulSoup and FinViz

I'm getting stuck trying to grab the text values off the a.href tags. I've managed to isolate the the target values but keep running into an error when I try to get_text().
import requests
from bs4 import BeautifulSoup
base_url = 'http://finviz.com/screener.ashx?v=152&s=ta_topgainers&o=price&c=0,1,2,3,4,5,6,7,25,63,64,65,66,67'
html = requests.get(base_url)
soup = BeautifulSoup(html.content, "html.parser")
main_div = soup.find('div', attrs = {'id':'screener-content'})
table = main_div.find('table')
sub = table.findAll('tr')
rows = sub[5].findAll('td')
for row in rows:
data = row.a
print data
Assuming you are actually trying to print data.get_text(), it would fail for some of the row in rows - because, in some cases, there are no child link elements in the td cells. You can check that a link was found beforehand:
for row in rows:
link = row.a
if link is not None:
print(link.get_text())
Note that "row" and "rows" are probably not the best variable names since you are actually iterating over the "cells" - td elements.

Parsing html data into python list for manipulation

I am trying to read in html websites and extract their data. For example, I would like to read in the EPS (earnings per share) for the past 5 years of companies. Basically, I can read it in and can use either BeautifulSoup or html2text to create a huge text block. I then want to search the file -- I have been using re.search -- but can't seem to get it to work properly. Here is the line I am trying to access:
EPS (Basic)\n13.4620.6226.6930.1732.81\n\n
So I would like to create a list called EPS = [13.46, 20.62, 26.69, 30.17, 32.81].
Thanks for any help.
from stripogram import html2text
from urllib import urlopen
import re
from BeautifulSoup import BeautifulSoup
ticker_symbol = 'goog'
url = 'http://www.marketwatch.com/investing/stock/'
full_url = url + ticker_symbol + '/financials' #build url
text_soup = BeautifulSoup(urlopen(full_url).read()) #read in
text_parts = text_soup.findAll(text=True)
text = ''.join(text_parts)
eps = re.search("EPS\s+(\d+)", text)
if eps is not None:
print eps.group(1)
It's not a good practice to use regex for parsing html. Use BeautifulSoup parser: find the cell with rowTitle class and EPS (Basic) text in it, then iterate over next siblings with valueCell class:
from urllib import urlopen
from BeautifulSoup import BeautifulSoup
url = 'http://www.marketwatch.com/investing/stock/goog/financials'
text_soup = BeautifulSoup(urlopen(url).read()) #read in
titles = text_soup.findAll('td', {'class': 'rowTitle'})
for title in titles:
if 'EPS (Basic)' in title.text:
print [td.text for td in title.findNextSiblings(attrs={'class': 'valueCell'}) if td.text]
prints:
['13.46', '20.62', '26.69', '30.17', '32.81']
Hope that helps.
I would take a very different approach. We use LXML for scraping html pages
One of the reasons we switched was because BS was not being maintained for a while - or I should say updated.
In my test I ran the following
import requests
from lxml import html
from collections import OrderedDict
page_as_string = requests.get('http://www.marketwatch.com/investing/stock/goog/financials').content
tree = html.fromstring(page_as_string)
Now I looked at the page and I see the data is divided into two tables. Since you want EPS, I noted that it is in the second table. We could write some code to sort this out programmatically but I will leave that for you.
tables = [ e for e in tree.iter() if e.tag == 'table']
eps_table = tables[-1]
now I noticed that the first row has the column headings, so I want to separate all of the rows
table_rows = [ e for e in eps_table.iter() if e.tag == 'tr']
now lets get the column headings:
column_headings =[ e.text_content() for e in table_rows[0].iter() if e.tag == 'th']
Finally we can map the column headings to the row labels and cell values
my_results = []
for row in table_rows[1:]:
cell_content = [ e.text_content() for e in row.iter() if e.tag == 'td']
temp_dict = OrderedDict()
for numb, cell in enumerate(cell_content):
if numb == 0:
temp_dict['row_label'] = cell.strip()
else:
dict_key = column_headings[numb]
temp_dict[dict_key] = cell
my_results.append(temp_dict)
now to access the results
for row_dict in my_results:
if row_dict['row_label'] == 'EPS (Basic)':
for key in row_dict:
print key, ':', row_dict[key]
row_label : EPS (Basic)
2008 : 13.46
2009 : 20.62
2010 : 26.69
2011 : 30.17
2012 : 32.81
5-year trend :
Now there is still more to do, for example I did not test for squareness (number of cells in each row is equal).
Finally I am a novice and I suspect others will advise more direct methods of getting at these elements (xPath or cssselect) but this does work and it gets you everything from the table in a nice structured manner.
I should add that every row from the table is available, they are in the original row order. The first item (which is a dictionary) in the my_results list has the data from the first row, the second item has the data from the second row etc.
When I need a new build of lxml I visit a page maintained by a really nice guy at UC-IRVINE
I hope this helps
from bs4 import BeautifulSoup
import urllib2
import lxml
import pandas as pd
url = 'http://markets.ft.com/research/Markets/Tearsheets/Financials?s=CLLN:LSE&subview=BalanceSheet'
soup = BeautifulSoup(urllib2.urlopen(url).read())
table = soup.find('table', {'data-ajax-content' : 'true'})
data = []
for row in table.findAll('tr'):
cells = row.findAll('td')
cols = [ele.text.strip() for ele in cells]
data.append([ele for ele in cols if ele])
df = pd.DataFrame(data)
print df
dictframe = df.to_dict()
print dictframe
The above code will give you a DataFrame from the webpage and then uses that to create a python dictionary.

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