Using delimiter in Python to cut out middle section

Question

I have a text file that is comma-separated with five different columns but I only want to get back the first column and the fourth column.

When I am using the split function it is just splitting everything and I don't know how to get it so that it will just take the first column and then skip to the fourth column.

This is an example of the data I am trying to organise:

11.332,2,2,-465,0.928621379033569

What I would like to get back from this is 11.332 and -465 and forget about the rest of it

Answer 1

There are a few ways to do it.

Your question is tagged with csv . You can parse CSV data with the csv module:

import csv

with open('file.csv') as f:
    for row in csv.reader(f):
        print(row[0])    # the first field
        print(row[3])    # the third field

For your sample data this would print:

11.332
-465

csv.reader() is probably the best way to go, however, another method is to use tuple unpacking with _ to denote ignored fields:

line = '11.332,2,2,-465,0.928621379033569'
first, _, _, fourth, _ = line.split(',')
print(first)
print(fourth)
# 11.332
# -465

Of course there is nothing stopping you from binding all of the fields to variables, just replace _ with a meaningful variable name.

Alternatively you can split the whole line and then pluck out the fields that you want by subscripting:

line = '11.332,2,2,-465,0.928621379033569'
data = '11.332,2,2,-465,0.928621379033569'.split(',')
print(data[0])
print(data[3])
# 11.332
# -465

Or you could use operator.itemgetter (combined with tuple unpacking):

from operator import itemgetter

fields = itemgetter(0, 3)
first, fourth = fields(line.split(','))
print first
print fourth
# 11.332
# -465

Answer 2

I managed to figure it out

for line in eda:
    print (line.split(',')[0])
    print (line.split(',')[3])

This is giving me out the two results that i need and forgetting about the rest of them