Getting numbers into a column in Python

I have a bunch of numbers that are tab-delimited with new line characters that looks something like this:

104     109     105     110     126     119      97     103\n
114     129     119     130     122     106     117     128\n

and so on. How can I use python to write all these numbers to a file in one column? i.e.

104\n
109\n
105\n
110\n
126\n

and so on. Fairly new to python so开发者_C百科 any help is appreciated, thanks!

---

The easiest way to do this is probably to use sed. But if you must use Python, you need to replace all tab characters with newlines. Try something like this:

with open('input_file', 'rb') as infile:
    with open('output_file', 'wb') as outfile:
        for line in infile:
            outfile.write(line.replace('\t', '\n'))

---

"\n".join("104 109 105 110 126 119 97 103\n 114 129 119 130 122 106 117 128\n".split())

---

There are multiple ways of tackling this problem. You could use string.split and string.join, but that seems inefficient, since you'd be converting a string into a tuple and back into a string.

Using regex, we replace one or more whitespace characters with a newline. The metacharacter \s represents any whitespace character), which in Python 2.7.1 is equivalent to [ \t\n\r\f\v] (and possibly additional whitespace characters, if UNICODE is set).

import re 

input_file = open('input_filename','r')
output_file = open('output_filename', 'w')
for line in input_file:
    output_file.write(re.sub('[\s]+','\n', line))
input_file.close()
output_file.close()

---

If your file is small, you can use file.readlines() to read all the lines into memory:

with open('input.txt', 'r') as fin:
    for row in [l.split() for l in fin.readlines()]:
        for col in row:
            print col

If the file is very large, read the lines into memory one at a time (I like to use a generator):

for row in open('input.txt'):
    for col in row.split():
        print col

In either case you can pipe the output to a new file:

python myscript.py >output.txt

---

Replace input_filename and output_filename with appropriate values.

f = open('input_filename','r')
nums = f.read().split()
f.close()
f = open('output_filename', 'w')
f.write('\n'.join(nums))
f.close()

[Edit] Reworked example that doesn't load the whole file into memory. It is now very similar to Chinmay Kanchi's example. But I use split where he uses replace.

with open('input_filename','r') as input:
    with open('output_filename', 'w') as output:
        for line in input:
            output.write('\n'.join(line.split()))
            output.write('\n')