Print to the same line and not a new line?

Question

Basically I want to do the opposite of what this guy did... hehe.

Python Script: Print new line each time to shell rather than update existing line

I have a program that is telling me how far along it is.

for i in some_list:     #do a bunch of stuff.     print i/len(some_list)*100," percent complete" 

So if len(some_list) was 50, I'd get that last line printed 50 times over. I want to print one line and keep updating that line. I know I know this is probably the lamest question you'll read all day. I just can't figure out the four words I need to put into google to get the answer.

Update! I tried mvds' suggestion which SEEMED right. The new code

print percent_complete,"           \r", 

Percent complete is just a string (I was abstracting the first time now I an trying to be literal). The result now is that it runs the program, doesn't print ANYTHING until after the program is over, and then prints "100 percent complete" on one and only one line.

Without the carriage return (but with the comma, half of mvds' suggestion) it prints nothing until the end. And then prints:

0 percent complete     2 percent complete     3 percent complete     4 percent complete     

And so on. So now the new issue is that with the comma it doesn't print until the program is finished.

With the carriage return and no comma it behaves the exact same as with neither.

Answer 1

It's called the carriage return, or \r

Use

print i/len(some_list)*100," percent complete         \r", 

The comma prevents print from adding a newline. (and the spaces will keep the line clear from prior output)

Also, don't forget to terminate with a print "" to get at least a finalizing newline!

Answer 2

From python 3.x you can do:

print('bla bla', end='') 

(which can also be used in Python 2.6 or 2.7 by putting from __future__ import print_function at the top of your script/module)

Python console progressbar example:

import time  # status generator def range_with_status(total):     """ iterate from 0 to total and show progress in console """     n=0     while n<total:         done = '#'*(n+1)         todo = '-'*(total-n-1)         s = '<{0}>'.format(done+todo)         if not todo:             s+='\n'                 if n>0:             s = '\r'+s         print(s, end='')         yield n         n+=1  # example for use of status generator for i in range_with_status(10):     time.sleep(0.1)