spliting text files using python

Question

I´m new in reading text files using python. I need to read a file which have in each line 4 data that I need, here is my text file

1 -10 0 0    
2 -10 -10 0    
3 0 -10 0    
4 10 -10 0    
5 10 0 0    
6 0 0 0

my problem is, that if I use read().splitlines(), it only creates a vector with each line, but I need a vector only for the first column, one for the second, one for the third, and also one for the fourth column. Con anyone help me please?

look [here](http://stackoverflow.com/questions/16503560/read-specific-columns-from-a-csv-file-with-csv-module) and [here](http://stackoverflow.com/questions/5741518/reading-each-column-from-csv-file). — bunji, Jan 27 '17 at 19:33
do you mean you need a vector for each column? example [1,2,3,4,5,6] , [-10,-10,0,10,10,0] — Md Sifatul Islam, Jan 27 '17 at 19:34

James · Accepted Answer · 2017-01-27T19:35:17.853

0

Try this. It open the file for reading as the file pointer fp. It looks at each line, one at a time, removes the newline characters, splits the line into a list on the space character, then converts each element in the list to an integer. In then forms a list of all of the lists of integers and stores it as the variable data.

with open('filename.txt', 'r') as fp:
    data = [list(map(int, line.strip().split(' '))) for line in fp]

edited Jan 27 '17 at 19:35

answered Jan 27 '17 at 19:31

James

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4
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1

Why? What does it do? – Alastair McCormack Jan 27 '17 at 19:33
I added an explanation. – James Jan 27 '17 at 19:35
James, thanks. That was very useful. – j.p Jan 30 '17 at 14:04

score 0 · Answer 2 · answered Jan 27 '17 at 19:34

First we make the list of strings that splitlines gives us into a list of lists. Then we can use zip to make tuples of those elements that share indices in those lists.

list(zip(*map(str.split, f.read().splitlines())))

for your input:

[('1', '2', '3', '4', '5', '6'), ('-10', '-10', '0', '10', '10', '0'),
 ('0', '-10', '-10', '-10', '0', '0'), ('0', '0', '0', '0', '0', '0')]

spliting text files using python

2 Answers2