CODEWITHSUNDEEP
pythonlistcsv
Chan Yong sheng
Chan Yong sheng

Reputation: 11

How do i delete a row from my csv file that fits my condition and write to a new output file

For example, i have the following dataset :

Date,Category,Amount,Description
06-06-2022,Food,300.0,celebration
02-09-2021,transport,3300.0,operation

And am required to delete one of the entries when condition 1 (e.g. description) and condition 2 (e.g. category) are met to get the following:

Date,Category,Amount,Description
06-06-2022,Food,300.0,celebration

so far, i have no issues with the conditions statement. However, when i execute, it would produced an output for the first line with commas for each individual character and no other info.

import os
import csv

with open("filename.csv","r+") as r, open("output.csv","w") as f:
     writer=csv.writer(f)
     for line in r:
            if condition_1 in line and condition_2 in line:
                print(line) #show the line that will be deleted
            else:
                writer.writerow(line) #write other lines to new file
                

os.remove('filename.csv')
os.rename('output.csv', "filename.csv")

Any help or tips would be appreciated!

Upvotes: 1

Views: 631

Answers (2)

nihilok
nihilok

Reputation: 2063

You already have a string of comma separated values in your line variable. You don't need the csv writer.

Instead you could try opening the file in append open('output.csv', 'a') mode and use f.write(line)

EDIT:

full code (working)

import os

with open("filename.csv", "r") as r, open("output.csv", "a") as f:
    for line in r:
        if 'transport' in line and '3300.0' in line:
            print(line)  # show the line that will be deleted
        else:
            f.write(line)  # write other lines to new file

os.remove('filename.csv')
os.rename('output.csv', "filename.csv")

Upvotes: 0

Huy
Huy

Reputation: 822

csv is an useful built-in standard library. With regards to learning it, you forgot to include csv.reader. Simply pass the file as an object to csv.reader similar to what you've done with csv.writer.

This is a working solution that you might want:

# import os
import csv

with open("filename.csv","r+") as r, open("output.csv","w") as f:
    # pass the file object to reader() to get the reader object
    reader = csv.reader(r)
    writer = csv.writer(f)
    # Iterate over each row in the csv using reader object
    for row in reader:
        # row variable is a list that represents a row in csv
        # print(row)
        # print row as original text line
        # print(', '.join(row))
        if row[0] == '06-06-2022' and row[1] == 'Food':
            print(f'{row} to be deleted') #show the line that will be deleted
        else:
            writer.writerow(row)
        
# os.remove('filename.csv')
# os.rename('output.csv', "filename.csv")

Try it here https://replit.com/@huydhoang/Delete-row-from-csv#main.py

Upvotes: 1

Related Questions