Parsing out single column from csv into text file using python

问题

I finally got my dbf file to be a csv but now I am confused as to how to parse this out into a text file for further editing.

I have been reading up on the csv module but to be honest my head began to spin. So much of it seemed Greek to me. However, I would like the code for using module this if possible.

My car.csv file looks like this:

Name,Total,Freq
Toyota,2,2
Mazda,1,1
Kia,2,1
Volkswagon,3,1

I want to output the following sentence into a text file (or csv):

Within this neighborhood there is a Toyota, Mazda, Kia, and Volkswagon parked on the street.

If the results are two I do not want commas:

Cars.dbf

Toyota,2,2
Mazda,2,1

Within this neighborhood there is a Toyota and Mazda parked on the street.

Cars.dbf

empty

There are no cars parked on the street within this neighborhood.

I got a good suggestion from a previous post on constructing the if-else sentences but am lost on how to parse columns (they didn't show up in Excel for some reason, I thought I only had one column)

python 2.7

BTW. Anyone know of a good web site that explains the csv module in terms a total newbie can understand? Thanks.

回答1:

The Python doc examples are always a go to place.

You want something like this:

import csv

makes = []
with open('cars.csv', 'rb') as f:
    reader = csv.reader(f)
    next(reader) # Ignore first row

    for row in reader:
        makes.append(row[0])

print makes

回答2:

Using the csv module:

>>> with open('cars.csv') as f:
...    reader = csv.reader(f)
...    cars_list = [row[0] for row in reader]
...
>>> cars_list
['Name', 'Toyota', 'Mazda', 'Kia', 'Volkswagon']

回答3:

if I'm understanding correctly, you already have the csv file. If so, all you need to do is read it into whatever function(s) you're using to process it. Here's an example:

def process_csv():
    with open('/path/to/file/car.csv') as f:
        for line in f:
            values_list = line.split(',') #gives you a list
            #process your the rest here.

Basically, this loads your file and creates a list from each line. So for your Toyota,2,2, you would end up with

> print('Name = " + values_list[0]) Name = Toyota

来源：https://stackoverflow.com/questions/15035660/parsing-out-single-column-from-csv-into-text-file-using-python

标签

python

csv

python-2.7

text-parsing