Daniel Bader: How to Use Python’s Print() Without Adding an Extra New Line

How to Use Python’s Print() Without Adding an Extra New Line

Here’s how you can avoid superfluous newlines when using the print function or statement in Python 2.x and 3.x

Let’s say you’re working on a Python script that prints out progress updates to the console while it does its work in order to keep the user informed.

Maybe you’ll want the output to look something like this:

Processing files
................
Complete

With another . dot printed every time a file has been processed. Now how would you implement this in Python?

If you try the following, you’ll get a botched output:

print('Processing files')

for i in range(5):
    print('.')

print('Complete')

Processing files
.
.
.
.
.
Complete

As you can see, the . dot characters are printed on a new line each instead of one long consecutive line. How do you get Python to print them all on one line without newlines after each character?

Python 2.x and 3.x – sys.stdout.write()

import sys

print('Processing files')

for i in range(5):
    sys.stdout.write('.')

print('Complete')

If you want to use sys.stdout.write for printing the other messages as well, you’ll need to make sure to add the newlines manually yourself. You can do this by adding a \n linefeed special character to your message strings, like so:

import sys

sys.stdout.write('Processing files\n')

for i in range(5):
    sys.stdout.write('.')

sys.stdout.write('Complete\n')

Depending on your terminal setup you might not see those dots printed immediately if you’re working with a bit of a delay between printing each characters. If this happens you can call the sys.stdout.flush() function to ensure any pending characters are written to the console.

Python 3.x – print() function

Python 2.x – print statement

Let’s say you wanted to print the following string of numbers in Python:

1, 2, 3, 4, 5

>>> for i in range(5):
...    print(i + ', ')
0,
1,
2,
3,
4,

132 down vote accepted In Python 3.x, you can use the end argument to the print() function to prevent a newline character from being printed:

print(“Nope, that is not a two. That is a”, end=”“) In Python 2.x, you can use a trailing comma:

print “this should be”, print “on the same line” You don’t need this to simply print a variable, though:

print “Nope, that is not a two. That is a”, x Note that the trailing comma still results in a space being printed at the end of the line, i.e. it’s equivalent to using end=” ” in Python 3. To suppress the space character as well, you can either use

from future import print_function to get access to the Python 3 print function or use sys.stdout.write().

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