How to remove empty lines with or without whitespace in Python

Question

I have large string which I split by newlines. How can I remove all lines that are empty, (whitespace only)?

pseudo code:

for stuff in largestring:
          


        

Answer 1

Same as what @NullUserException said, this is how I write it:

removedWhitespce = re.sub(r'^\s*$', '', line)

Answer 2

you can simply use rstrip:

    for stuff in largestring:
        print(stuff.rstrip("\n")

Answer 3

Surprised a multiline re.sub has not been suggested (Oh, because you've already split your string... But why?):

>>> import re
>>> a = "Foo\n \nBar\nBaz\n\n   Garply\n  \n"
>>> print a
Foo

Bar
Baz

        Garply


>>> print(re.sub(r'\n\s*\n','\n',a,re.MULTILINE))
Foo
Bar
Baz
        Garply

>>> 

Answer 4

If you are not willing to try regex (which you should), you can use this:

s.replace('\n\n','\n')

Repeat this several times to make sure there is no blank line left. Or chaining the commands:

s.replace('\n\n','\n').replace('\n\n','\n')

_{Just to encourage you to use regex, here are two introductory videos that I find intuitive:
• Regular Expressions (Regex) Tutorial
• Python Tutorial: re Module}

Answer 5

I also tried regexp and list solutions, and list one is faster.

Here is my solution (by previous answers):

text = "\n".join([ll.rstrip() for ll in original_text.splitlines() if ll.strip()])

Answer 6

My version:

while '' in all_lines:
    all_lines.pop(all_lines.index(''))