Question

I’m new to scripting. I have a table (Table1.txt) and I need to create another table that has Table1’s rows arranged in columns and vice versa. I have found solutions to this problem for Perl and SQL but not for Python.

I just started learning Python two days ago, so this is as far as I got:

import csv
import sys

with open(sys.argv[1], "rt") as inputfile:
   readinput = csv.reader(inputfile, delimiter='\t')
   with open("output.csv", 'wt') as outputfile:
      writer = csv.writer(outputfile, delimiter="\t")
      for row in readinput:
            values = [row[0], row[1], row[2], row[3]]
            writer.writerow([values])

This just reproduces the columns as columns. What I would have liked to do now is to write the last line as writer.writecol([values]) but it seems that there is no command like that and I haven’t found another way of writing rows as columns.

Answer 1

The solution in general to transpose a sequence of iterables is: zip(*original_list)

sample input:

1   2   3   4   5
6   7   8   9   10
11  12  13  14  15

program:

with open('in.txt') as f:
  lis = [x.split() for x in f]

for x in zip(*lis):
  for y in x:
    print(y+'\t', end='')
  print('\n')

output:

1   6   11  

2   7   12  

3   8   13  

4   9   14  

5   10  15