python - How to clear the interpreter console?

Question

Like most Python developers, I typically keep a console window open with the Python interpreter running to test commands, dir() stuff, help() stuff, etc.

Like any console, after a while the visible backlog of past commands and prints gets to be cluttered, and sometimes confusing when re-running the same command several times. I'm wondering if, and how, to clear the Python interpreter console.

I've heard about doing a system call and either calling cls on Windows or clear on Linux, but I was hoping there was something I could command the interpreter itself to do.

Note: I'm running on Windows, so Ctrl+L doesn't work.

Answer 1

As you mentioned, you can do a system call:

For Windows:

>>> import os
>>> clear = lambda: os.system('cls')
>>> clear()

For Linux it would be:

>>> import os
>>> clear = lambda: os.system('clear')
>>> clear()

Answer 2

here something handy that is a little more cross-platform

import os

def cls():
    os.system('cls' if os.name=='nt' else 'clear')

# now, to clear the screen
cls()

Answer 3

Well, here's a quick hack:

>>> clear = "\n" * 100
>>> print clear
>>> ...do some other stuff...
>>> print clear

Or to save some typing, put this file in your python search path:

# wiper.py
class Wipe(object):
    def __repr__(self):
        return '\n'*1000

wipe = Wipe()

Then you can do this from the interpreter all you like :)

>>> from wiper import wipe
>>> wipe
>>> wipe
>>> wipe

Answer 4

You have number of ways doing it on Windows:

1. Using Keyboard shortcut:

Press CTRL + L

2. Using system invoke method:

import os
cls = lambda: os.system('cls')
cls()

3. Using new line print 100 times:

cls = lambda: print('\n'*100)
cls()

Answer 5

Although this is an older question, I thought I'd contribute something summing up what I think were the best of the other answers and add a wrinkle of my own by suggesting that you put these command(s) into a file and set your PYTHONSTARTUP environment variable to point to it. Since I'm on Windows at the moment, it's slightly biased that way, but could easily be slanted some other direction.

Here's some articles I found that describe how to set environment variables on Windows:
    When to use sys.path.append and when modifying %PYTHONPATH% is enough
    How To Manage Environment Variables in Windows XP
    Configuring System and User Environment Variables
    How to Use Global System Environment Variables in Windows

BTW, don't put quotes around the path to the file even if it has spaces in it.

Anyway, here's my take on the code to put in (or add to your existing) Python startup script:

# ==== pythonstartup.py ====

# add something to clear the screen
class cls(object):
    def __repr__(self):
        import os
        os.system('cls' if os.name == 'nt' else 'clear')
        return ''

cls = cls()

# ==== end pythonstartup.py ====

BTW, you can also use @Triptych's __repr__ trick to change exit() into just exit (and ditto for its alias quit):

class exit(object):
    exit = exit # original object
    def __repr__(self):
        self.exit() # call original
        return ''

quit = exit = exit()

Lastly, here's something else that changes the primary interpreter prompt from >>> to cwd+>>>:

class Prompt:
    def __str__(self):
        import os
        return '%s >>> ' % os.getcwd()

import sys
sys.ps1 = Prompt()
del sys
del Prompt

Answer 6

Quickest and easiest way without a doubt is Ctrl+L.

This is the same for OS X on the terminal.

Answer 7

This is the simplest thing you can do and it doesn't require any additional libraries. It will clear the screen and return >>> to the top left corner.

print("\033[H\033[J")

Answer 8

my way of doing this is to write a function like so:

import os
import subprocess

def clear():
    if os.name in ('nt','dos'):
        subprocess.call("cls")
    elif os.name in ('linux','osx','posix'):
        subprocess.call("clear")
    else:
        print("\n") * 120

then call clear() to clear the screen. this works on windows, osx, linux, bsd... all OSes.

Answer 9

Here's a cross platform (Windows / Linux / Mac / Probably others that you can add in the if check) version snippet I made combining information found in this question:

import os
clear = lambda: os.system('cls' if os.name=='nt' else 'clear')
clear()

Same idea but with a spoon of syntactic sugar:

import subprocess   
clear = lambda: subprocess.call('cls||clear', shell=True)
clear()

Answer 10

Wiper is cool, good thing about it is I don't have to type '()' around it. Here is slight variation to it

# wiper.py
import os
class Cls(object):
    def __repr__(self):
        os.system('cls')
        return ''

The usage is quite simple:

>>> cls = Cls()
>>> cls # this will clear console.

Answer 11

for the mac user inside the python console type

import os
os.system('clear')

for windows

os.system('cls')

Answer 12

The perfect cls:

cls = lambda: print("\033c\033[3J", end='')
cls()

Or directly:

print("\033c\033[3J", end='')

Answer 13

I'm not sure if Windows' "shell" supports this, but on Linux:

print "\033[2J"

https://en.wikipedia.org/wiki/ANSI_escape_code#CSI_codes

In my opinion calling cls with os is a bad idea generally. Imagine if I manage to change the cls or clear command on your system, and you run your script as admin or root.

Answer 14

Here's the definitive solution that merges all other answers. Features:

1. You can copy-paste the code into your shell or script.

2. You can use it as you like:

   >>> clear()
   >>> -clear
   >>> clear  # <- but this will only work on a shell
   

3. You can import it as a module:

   >>> from clear import clear
   >>> -clear
   

4. You can call it as a script:

   $ python clear.py
   

5. It is truly multiplatform; if it can't recognize your system
   (ce, nt, dos or posix) it will fall back to printing blank lines.

---

You can download the [full] file here: https://gist.github.com/3130325
Or if you are just looking for the code:

class clear:
 def __call__(self):
  import os
  if os.name==('ce','nt','dos'): os.system('cls')
  elif os.name=='posix': os.system('clear')
  else: print('\n'*120)
 def __neg__(self): self()
 def __repr__(self):
  self();return ''

clear=clear()

Answer 15

I use iTerm and the native terminal app for Mac OS.

I just press ⌘ + k

Answer 16

Use idle. It has many handy features. Ctrl+F6, for example, resets the console. Closing and opening the console are good ways to clear it.

Answer 17

If you don't need to do it through code, just press CTRL+L

Answer 18

The easiest way is to use os module

>>> import os
>>> clear = lambda: os.system('clear')
>>> clear()

Answer 19

I'm using MINGW/BASH on Windows XP, SP3.

(stick this in .pythonstartup)
# My ctrl-l already kind of worked, but this might help someone else
# leaves prompt at bottom of the window though...
import readline
readline.parse_and_bind('\C-l: clear-screen')

# This works in BASH because I have it in .inputrc as well, but for some
# reason it gets dropped when I go into Python
readline.parse_and_bind('\C-y: kill-whole-line')

---

I couldn't stand typing 'exit()' anymore and was delighted with martineau's/Triptych's tricks:

I slightly doctored it though (stuck it in .pythonstartup)

class exxxit():
    """Shortcut for exit() function, use 'x' now"""
    quit_now = exit # original object
    def __repr__(self):
        self.quit_now() # call original
x = exxxit()

---

Py2.7.1>help(x)
Help on instance of exxxit in module __main__:

class exxxit
 |  Shortcut for exit() function, use 'x' now
 |
 |  Methods defined here:
 |
 |  __repr__(self)
 |
 |  ----------------------------------------------------------------------
 |  Data and other attributes defined here:
 |
 |  quit_now = Use exit() or Ctrl-Z plus Return to exit

Answer 20

The OS command clear in Linux and cls in Windows outputs a "magic string" which you can just print. To get the string, execute the command with popen and save it in a variable for later use:

from os import popen
with popen('clear') as f:
    clear = f.read()

print clear

On my machine the string is '\x1b[H\x1b[2J'.

Answer 21

I'm new to python (really really new) and in one of the books I'm reading to get acquainted with the language they teach how to create this little function to clear the console of the visible backlog and past commands and prints:

Open shell / Create new document / Create function as follows:

def clear():
    print('\n' * 50)

Save it inside the lib folder in you python directory (mine is C:\Python33\Lib) Next time you nedd to clear your console just call the function with:

clear()

that's it. PS: you can name you function anyway you want. Iv' seen people using "wiper" "wipe" and variations.

Answer 22

Here are two nice ways of doing that:

1.

import os

# Clear Windows command prompt.
if (os.name in ('ce', 'nt', 'dos')):
    os.system('cls')

# Clear the Linux terminal.
elif ('posix' in os.name):
    os.system('clear')

2.

import os

def clear():
    if os.name == 'posix':
        os.system('clear')

    elif os.name in ('ce', 'nt', 'dos'):
        os.system('cls')


clear()

Answer 23

Just enter

import os
os.system('cls') # Windows
os.system('clear') # Linux, Unix, Mac OS X

Answer 24

If it is on mac, then a simple cmd + k should do the trick.

Answer 25

Arch Linux (tested in xfce4-terminal with Python 3):

# Clear or wipe console (terminal):
# Use: clear() or wipe()

import os

def clear():
    os.system('clear')

def wipe():
    os.system("clear && printf '\e[3J'")

... added to ~/.pythonrc

• clear() clears screen
• wipe() wipes entire terminal buffer

Answer 26

EDIT: I've just read "windows", this is for linux users, sorry.

---

In bash:

#!/bin/bash

while [ "0" == "0" ]; do
    clear
    $@
    while [ "$input" == "" ]; do
        read -p "Do you want to quit? (y/n): " -n 1 -e input
        if [ "$input" == "y" ]; then
            exit 1
        elif [ "$input" == "n" ]; then
            echo "Ok, keep working ;)"
        fi
    done
    input=""
done

Save it as "whatyouwant.sh", chmod +x it then run:

./whatyouwant.sh python

or something other than python (idle, whatever). This will ask you if you actually want to exit, if not it rerun python (or the command you gave as parameter).

This will clear all, the screen and all the variables/object/anything you created/imported in python.

In python just type exit() when you want to exit.

Answer 27

This should be cross platform, and also uses the preferred subprocess.call instead of os.system as per the os.system docs. Should work in Python >= 2.4.

import subprocess
import os

if os.name == 'nt':
    def clearscreen():
        subprocess.call("cls", shell=True)
        return
else:
    def clearscreen():
        subprocess.call("clear", shell=True)
        return

Answer 28

How about this for a clear

- os.system('cls')

That is about as short as could be!

Answer 29

I found the simplest way is just to close the window and run a module/script to reopen the shell.

Answer 30

>>> ' '*80*25

UPDATE: 80x25 is unlikely to be the size of console windows, so to get the real console dimensions, use functions from pager module. Python doesn't provide anything similar from core distribution.

>>> from pager import getheight
>>> '\n' * getheight()