split file with python into new lines with counter

Question

I want to split a file that contains a tab delimited list of words into a "list" with the word preceeded by a number.

So if the input file contains this (where the space between words is a tab): tree car house blanket

I'd like this output:

1 tree
2  car
3  house
4 blanket

I've got this code working that prints out the "list of words" but not sure how to get the counter in front of the words:

#!/usr/bin/env python

import csv

with open ("commonwords.tsv") as file:
  for line in file:
    print line.replace("\t","\n") 

Thanks

Answer 1

You can use enumerate :

import csv
with open("commonwords.tsv") as f:
    for line in f:
        line = line.replace("\t", "\n")
        for ind, word in enumerate(line.split(), 1):
            print "{0} {1}".format(ind, word)
1 tree
2 car
3 house
4 blanket

Not sure if you want the count to reset each line or continue to the end:

with open("commonwords.tsv") as f:
    line = f.read().replace("\t", "\n")
    for ind, word in enumerate(line.split(), 1):
        print "{0} {1}".format(ind, word)

You can also just split without replacing:

with open("commonwords.tsv") as f:
    lines = f.read().split()
    for ind, word in enumerate(lines, 1):
        print "{0} {1}".format(ind, word)

Answer 2

The enumerate function can count the words for you but you need an iterator or a list of the words, not just the lines of the file. Here's a generator that goes through rows of a csv file and outputs each column individually. its fed through enumerate to get the result.

import csv

def yield_col(reader):
    for row in reader:
        for item in row:
            yield item

with open ("commonwords.tsv") as fp:
    reader = csv.reader(fp, dialect='excel-tab')
    for num, word in enumerate(yield_col(reader), 1):
        print num, word

Answer 3

import csv
import itertools

with open('commonwords.tsv') as infile, open('/path/to/output', 'w') as outfile:
    writer = csv.writer(outfile, delimiter='\t')
    count = itertools.count(1)
    for row in csv.reader(infile, delimiter'\t'):
        for word in row:
            writer.writerow([next(count), word])