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Delete row or cell in a csv file

I want to delete rows from a csv file as they are processed.
My file:
Sr,Name1,Name2,Name3
1,Zname1,Zname2,Zname3
2,Yname1,Yname2,Yname3
3,Xname1,Xname2,Xname3
I want to read row by row and delete the row which has been processed.
So the file will be now:
2,Yname1,Yname2,Yname3
3,Xname1,Xname2,Xname3
The solutions which are provided on other questions are:
read the file
use next() or any other way to skip the row and write the remaining rows in an updated file
I want to delete the row from the original file which was entered in .reader() method
My code:
with open("file.txt", "r") as file
reader = csv.reader(file)
for row in reader:
#process the row
#delete the row
I have not been able to figure out how to delete/remove the row.
I want the change to be in the original file.txt because I will be running the program many times and so each time it runs, file.txt will already be present and the program will start from where it ended the last time.

Just read the csv file in memory as a list, then edit that list, and then write it back to the csv file.
lines = list()
members= input("Please enter a member's name to be deleted.")
with open('mycsv.csv', 'r') as readFile:
reader = csv.reader(readFile)
for row in reader:
lines.append(row)
for field in row:
if field == members:
lines.remove(row)
with open('mycsv.csv', 'w') as writeFile:
writer = csv.writer(writeFile)
writer.writerows(lines)
You can delete column like this:
We can use the panda pop () method to remove columns from CSV by naming the column as an argument.
Import Pandas.
Read CSV File.
Use pop() function for removing or deleting rows or columns from the CSV files.
Print Data.

You probably can find inspiration here: How to delete a specific line in a file?.
And don't forget to grant write permission when opening the file.

Since the pandas package deals with big data, there is no solution in basic Python.
You will have to import pandas.
import pandas
df=pandas.read_csv("file_name.txt")
df.set_value(0,"Name3",new_value)
df.to_csv("file_name.txt", index=False)
This code edits the cell in the 0th row and Name3 column. The 0th row is the first row below the header. Thus, Zname3 will be changed to something else. You can similarly delete a row or a cell.
I have not tried this code but it is supposed to work in the required manner.

Issue with using the zip function and writerows to create a CSV file

I am relatively new to python (3 weeks in) and am trying to create some code of scrape some data from a webpage. I have been able to use xpath to create some lists of data. So here I have a list of offices and a list of contacts.
In order to combine them, I used the zip function as you see below. If I print the list(test) I can see that I get an expected result of a list with a bunch of tuples such as
[('\n101 Venture', '\nJeremy Baron'), ('\n1888 Management', '\nTrent May'), ('\n1919 Investment Counsel', "\nHarry O'Mealia"), ('\n2M Companies', '\nAmeeth Sankaran')]
Felt I was on the correct path based on this question: Write a csv file in Python : error with function writerows
However, the CSV File comes up empty whenever I open it. Here is my code:
# combine lists from scraper
test = zip(office, contact_name)
#make CSV
with open('some3.csv', 'wt') as csvfile:
csv_out = csv.writer(csvfile)
csv_out.writerows(test)
So not sure why I am not generating a CSV file with each tuple as a row and each element separated by a comma in the file.

Solved by doing this:
test = zip(office, contact_name)
#make CSV
with open('some6.csv', 'w+', newline="") as csvfile:
csv_out = csv.writer(csvfile, delimiter=",")
for row in test:
csv_out.writerow(row)

Python: Trying to extract and output rows from one csv file to another csv file

As per the title, I'm attempting to write a python script to read a csv file, filter through it to see which ones I need and output the filtered rows into a seperate csv file.
So far I am able to read the csv files with:
open('list.csv') as f
csv_f = csv.reader(f)
and I am storing 3 of the rows in a tuple and using it to compare it to another list to see if there is a match. If there is a match I want the row containing the tuple to output to a new csv file.
I have successfully been able to read the files, match the tuples with another list and output which have been matched as text. The problem is I do not know how to then output the rows that match the tuple into a new csv file.
I was thinking to assign a row number to each tuple but that did not go anywhere either.
I want to know the best way I can effectively output the rows I need

Using csv module, this could be a solution more elegant:
with open('input.csv', 'r') as inp, open('output', 'w') as outp:
csv_f = csv.reader(inp)
csv_o = csv.reader(outp)
for line in csv_f:
if line == 'something':
csv_o.writeline(line)

Open both files. Iterate through the lines in the file that you read from and case your condition evaluates to True, then write the line to the output file.
with open('list.csv', 'r') as rf:
with open('output.csv', 'w') as wf:
# Read lines
for read_line in rf:
if <your condition>:
# Write to the file
wf.write(read_line)

add row to a csv file with python

I have two csv files that each have 2 columns, one of them being the date. I want to add the second column of the second file to the first file, resulting a file with 3 columns.
I did it by creating a new file and appending the data to it this way:
import csv
coinsfile = open('total-bitcoins.csv', newline='')
pricesfile = open('market-price.csv', newline='')
coins = csv.reader(coinsfile, delimiter=',')
prices = csv.reader(pricesfile, delimiter=',')
with open('result.csv', 'w') as res:
for coin_row, price_row in zip(coins, prices):
line = str(coin_row[0]) + ',' + str(coin_row[1]) + ',' + str(price_row[1])
res.append(line)
The code runs without any errors but the result is a csv file which is completely empty.
Where am I making the mistake, or is there a better way to do this job?

res is a file handle, so the append method doesn't apply to it. So there's an attribute error while the output file is opened, which results in an empty output file (or, yes, one of the input files is empty, ending zip immediately, but this answer explains how to fix the next issues)
A quickfix would be:
res.write(line+"\n")
but the best way would be to flatten the result of zip and feed it to a csv.writer object (using a comprehension to generate each row by addition of both input csv rows)
import csv
with open('result.csv', 'w', newline="") as res, open('total-bitcoins.csv', newline='') as coinsfile, open('market-price.csv', newline='') as pricesfile:
coins = csv.reader(coinsfile)
prices = csv.reader(pricesfile)
cw = csv.writer(res)
cw.writerows(coin_rows+price_row for coin_row, price_row in zip(coins, prices))
note that newline="" is required when writing your files (Python 3) to avoid the infamous blank line "bug" when running windows
I have added the input files in the with statement to ensure that the inputs are closed when exiting it. And also removed the delimiter parameter as comma is the default.

The easiest way to satisfy this need would be using a library like pandas. Using pandas, adding a column to an existing file would be as easy as loading the file into a dataframe, and adding the required column to it in just one line.
Adding can be done by mere assignment, or through join/merge methods.

Trying to import a list of words using csv (Python 2.7)

import csv, Tkinter
with open('most_common_words.csv') as csv_file: # Opens the file in a 'closure' so that when it's finished it's automatically closed"
csv_reader = csv.reader(csv_file) # Create a csv reader instance
for row in csv_reader: # Read each line in the csv file into 'row' as a list
print row[0] # Print the first item in the list
I'm trying to import this list of most common words using csv. It continues to give me the same error
for row in csv_reader: # Read each line in the csv file into 'row' as a list
Error: new-line character seen in unquoted field - do you need to open the file in universal-newline mode?
I've tried a couple different ways to do it as well, but they didn't work either. Any suggestions?
Also, where does this file need to be saved? Is it okay just being in the same folder as the program?

You should always open a CSV file in binary mode (Python 2) or universal newline mode (Python 3). Also, make sure that the delimiters and quote characters are , and ", or you'll need to specify otherwise:
with open('most_common_words.csv', 'rb') as csv_file:
csv_reader = csv.reader(csv_file, delimiter=';', quotechar='"') # for EU CSV
You can save the file in the same folder as your program. If you don't, you can provide the correct path to open() as well. Be sure to use raw strings if you're on Windows, otherwise the backslashes may trick you: open(r"C:\Python27\data\table.csv")

It seems you have a file with one column as you say here:
It is a simple list of words. When I open it up, it opens into Excel
with one column and 500 rows of 500 different words.
If so, you don't need the csv module at all:
with open('most_common_words.csv') as f:
rows = list(f)
Note in this case, each item of the list will have the newline appended to it, so if your file is:
apple
dog
cat
rows will be ['apple\n', 'dog\n', 'cat\n']
If you want to strip the end of line, then you can do this:
with open('most_common_words.csv') as f:
rows = list(i.rstrip() for i in f)