Python Forum

I have to write a Python application to read a CSV input file (appsUsage.csv) and generate an output file counting the frequency of the apps usage per user. The first column of the input file contains user id (user_id) and the second column contains the name of the app (app_name). From appsUsage.csv, I have to count the frequency of apps usage on individual user basis to generate app_Rank, and transform to a new data set named appsIndividualUsage.csv with the following columns: user_id; app_name; app_Rank.
For example if appsUsage.csv has following events

a facebook a facebook a linkedin b google b yahoo b yahoo

Then appsIndividualUsage.csv would be:

a facebook 2; a linkedin 1; b google 1; b yahoo 2;

Here is my code that I am struggling with :

>>>import csv with open(‘C:\\Users\\anne\\Desktop\\appsUsage.csv’, mode='r') as f_in, open(‘C:\\Users\\anne\\Desktop\\appsIndividualUsage.csv’, mode='w', newline='') as f_out: 
f_reader = csv.reader(f_in, dialect=csv.excel_tab) 
f_writer = csv.writer(f_out, dialect=csv.excel_tab) 
for line in reader: 
if line is equal then write it in writer and add a row of frequency

i totally don't know how to write the last line of my code


If someone can help 


Thank you

Right off the bat, if you try to run the very first line
you will get

Error:
SyntaxError: invalid syntax

I'd fix that first

I would first use a source code editor instead of terminal/IDLE, no need for fancy IDEs as of now (Notepad++ is simple and good enough in your case). Working directly on terminal/IDLE isn't the best approach, and this seems what you're doing, as I can guess from your '>>>'. By using a source code editor you have more flexibility to edit and inspect the code as a whole.

In IDLE there are two modes,you always start in interactive shell.
To write code File -- > New File and run it with Run module(F5).

You can test with your code that i have clean up.
Added print(line)  if it work you see output.
Then figurere out columns.

import csv

app_in = 'C:\\Users\\anne\\Desktop\\appsUsage.csv'
app_out = 'C:\\Users\\anne\\Desktop\\appsIndividualUsage.csv'

with open(app_in) as f_in, open(app_out, 'w', newline='') as f_out:
    f_reader = csv.reader(f_in, dialect=csv.excel_tab)
    f_writer = csv.writer(f_out, dialect=csv.excel_tab)
    for line in reader:
        print(line)
        #if line is equal then write it in writer and add a row of frequency