通过更改标题将.csv文件中的单个列拆分为多个列，并使用Python 2将其保存到新的.csv文件中

Question

I have a .csv file named selected.csv in C:\\Users\\Win-8.1\\Desktop\\delhi that contains 3 columns:

 Entries        |       Date (LT)    | AQI | Raw Conc.
 First Entry        01-01-2016 00:00   316     322
 Last Entry         31-12-2016 24:00   316     264

Now, what I want to do is:

i) Copy the data from this .csv file into a new empty .csv file named corrected.csv which I have created in the same folder.

The desired output should look like:

  Entries     |          Date    |    Month    |   Hour   | AQI | Raw Conc.
 First Entry              1         January       12 AM    316     322
 Last Entry              31        December       11 PM    316     264

Answer 1

import csv
from datetime import datetime

output_file = open('C:\Users\Win-8.1\Desktop\delhi\corrected.csv', 'w')
fieldnames = ['Entries', 'Date', 'Month' , 'Hour', 'AQI' , 'Raw Conc']
writer = csv.DictWriter(output_file, fieldnames=fieldnames)
writer.writeheader()

with open('C:\Users\Win-8.1\Desktop\delhi\selected.csv') as csvfile:
    reader = csv.DictReader(csvfile)
    for row in reader:
        output_row = {}
        output_row['Entries'] = row['Entries']
        change_date = datetime.strptime(row['Date (LT)'], '%d-%m-%Y %H:%M')
        output_row['Date'] = change_date.strftime('%d')
        output_row['Month'] = change_date.strftime('%B')
        output_row['Hour'] = change_date.strftime('%I %p')
        output_row['AQI'] = row['AQI']
        output_row['Raw Conc'] = row['Raw Conc']
        writer.writerow(output_row)

output_file.close()

Note : I haven't tested the code so if you face any error let me know.

This is solution for your problem, but I would seriously suggest you to read more about Python CSV and Python Datetime library.This will help you for your future problem.

Answer 2

The working code to the posted question is as follows:

import csv
from datetime import datetime

output_file = open(r"C:\Users\Win-8.1\Desktop\delhi\corrected.csv", "wb")
fieldnames = ['Date', 'Month' , 'Year', 'Hour', 'AQI' , 'Raw Conc.']
writer = csv.DictWriter(output_file, fieldnames=fieldnames)
writer.writeheader()

with open(r"C:\Users\Win-8.1\Desktop\delhi\selected.csv") as csvfile:
    reader = csv.DictReader(csvfile)
    for row in reader:
        output_row = {}
        change_date = datetime.strptime(row['Date (LT)'], '%d-%m-%Y %H:%M')
        output_row['Date'] = change_date.strftime('%d')
        output_row['Month'] = change_date.strftime('%B')
        output_row['Year'] = change_date.strftime('%Y')
        output_row['Hour'] = change_date.strftime('%I %p')
        output_row['AQI'] = row['AQI']
        output_row['Raw Conc.'] = row['Raw Conc.']
        writer.writerow(output_row)

output_file.close()