ipython: how to set terminal width

Question

When I use ipython terminal and want to print a numpy.ndarray which has many columns, the lines are automatically broken somewhere around 80 characters (i.e. the width of the lines is cca 80 chars):

z = zeros((2,20)) print z 

Presumably, ipython expects that my terminal has 80 columns. In fact however, my terminal has width of 176 characters and I would like to use the full width.

I have tried changing the following parameter, but this has no effect:

c.PlainTextFormatter.max_width = 160 

How can I tell ipython to use full width of my terminal ?

I am using ipython 1.2.1 on Debian Wheezy

Answer 1

You can see your current line width with

numpy.get_printoptions()['linewidth'] 

and set it with

numpy.set_printoptions(linewidth=160) 

Automatically set printing width

If you'd like the terminal width to be set automatically, you can have Python execute a startup script. So create a file ~/.python_startup.py or whatever you want to call it, with this inside it:

# Set the printing width to the current terminal width for NumPy. # # Note: if you change the terminal's width after starting Python, #       it will not update the printing width. from os import getenv terminal_width = getenv('COLUMNS') try:     terminal_width = int(terminal_width) except (ValueError, TypeError):     print('Sorry, I was unable to read your COLUMNS environment variable')     terminal_width = None  if terminal_width is not None and terminal_width > 0:     from numpy import set_printoptions     set_printoptions(linewidth = terminal_width)  del terminal_width 

and to have Python execute this every time, open your ~/.bashrc file, and add

# Instruct Python to execute a start up script export PYTHONSTARTUP=$HOME/.python_startup.py # Ensure that the startup script will be able to access COLUMNS export COLUMNS 

Answer 2

After some digging through the code, it appears that the variable you're looking for is numpy.core.arrayprint._line_width, which is 75 by default. Setting it to 160 worked for me:

>>> numpy.zeros((2, 20)) array([[ 0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0., 0.,  0.,  0.,  0.],        [ 0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.,  0.]]) 

The function used by default for array formatting is numpy.core.numeric.array_repr, although you can change this with numpy.core.numeric.set_string_function.