CODEWITHSUNDEEP
pandasdataframecsvbeautifulsoup
SY5
SY5

Reputation: 15

How to convert HTML table to CSV? [Python]

I have a fixed stracture of data array that comes in a table I saved the html with the table now im trying to take the table that is inside the html file and put it in a csv file to organize the data (with a code I saw here) and im keep getting an error

this is the code (taken from this site)

# Importing the required modules 
import os
import sys
import pandas as pd
from bs4 import BeautifulSoup

path = 'file location' + 'file.html'

# empty list
data = []

# for getting the header from
# the HTML file
list_header = []
soup = BeautifulSoup(open(path),'html.parser')
header = soup.find_all("table")[0].find("tr")

for items in header:
    try:
        list_header.append(items.get_text())
    except:
        continue

# for getting the data 
HTML_data = soup.find_all("table")[0].find_all("tr")[1:]

for element in HTML_data:
    sub_data = []
    for sub_element in element:
        try:
            sub_data.append(sub_element.get_text())
        except:
            continue
    data.append(sub_data)

# Storing the data into Pandas
# DataFrame 
dataFrame = pd.DataFrame(data = data, columns = list_header)

# Converting Pandas DataFrame
# into CSV file
dataFrame.to_csv('Geeks.csv')

but get this error

File, line 38, in <module>
dataFrame = pd.DataFrame(data = data, columns = list_header)
File, line 509, in __init__
arrays, columns = to_arrays(data, columns, dtype=dtype)
File, line 524, in to_arrays
return _list_to_arrays(data, columns, coerce_float=coerce_float, dtype=dtype)
File, line 567, in _list_to_arrays
raise ValueError(e) from e
ValueError: 1 columns passed, passed data had 7 columns

what am I doing wrong ?

Upvotes: 1

Views: 2194

Answers (1)

Zach Young
Zach Young

Reputation: 11178

The big thing I see that's missing in your sample code is that you're not iterating td elements inside every row element, maybe the for sub_element in element line does the cell iteration, but it's not clear. For yourself, and anyone else who needs to read your code (like, us 🙂), I recommend being very explicit with finding and iterating elements.

I don't have BeautifulSoup (BS) or Pandas installed, but I'd like to offer the following as a template for explicitly traversing your table's hierarchy. I'm using Python's standard xml and csv modules. (I think the BS API is similar enough to ElementTree to guide you)

Here's a very simple HTML with a table, input.html:

<html>
<body>
<table>
    <tr><td>Col1</td><td>Col2</td><td>Col3</td></tr>
    <tr><td>Row1Col1</td><td>Row1Col2</td><td>Row1Col3</td></tr>
    <tr><td>Row2Col1</td><td>Row2Col2</td><td>Row2Col3</td></tr>
    <tr><td>Row3Col1</td><td>Row3Col2</td><td>Row3Col3</td></tr>
    <tr><td>Row4Col1</td><td>Row4Col2</td><td>Row4Col3</td></tr>
</table>
</body>
</html>

import csv
from xml.etree import ElementTree as ET

# Accumulate rows from the table
all_rows = []

root = ET.parse('input.html')

# Get the table once
my_table = root.find('.//table')

# Iterate rows (tr) for that table
for elem_tr in my_table.findall('tr'):
    new_row = []

    # Iterate cells (td) per row
    for elem_td in elem_tr.findall('td'):
        # Build your row cell-by-cell
        new_row.append(elem_td.text)

    # Save finished row
    all_rows.append(new_row)

# Finally write all rows
with open('out.csv', 'w', newline='') as f:
    writer = csv.writer(f)
    writer.writerows(all_rows)

When I run that, here's my out.csv:

Col1,Col2,Col3
Row1Col1,Row1Col2,Row1Col3
Row2Col1,Row2Col2,Row2Col3
Row3Col1,Row3Col2,Row3Col3
Row4Col1,Row4Col2,Row4Col3

Upvotes: 2

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