/matplotlib-backend-sixel

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matplotlib-backend-sixel

This python module allows you to use your sixel-enabled terminal to show inline plots generated by python's matplotlib.

The module is a modified version of the kitty backend and is also based on this earlier sixel backend.

You will need a terminal that has support for the SIXEL graphics format and imagemagick installed.

To install either run

  • $ pip install --user matplotlib-backend-sixel

or clone this repo and run

  • $ cd matplotlib-backend-sixel && pip install .

Configure matplotlib to use the module by either setting the environment variable MPLBACKEND to module://matplotlib-backend-sixel or by initializing matplotlib as follows.

import matplotlib
matplotlib.use('module://matplotlib-backend-sixel')
import matplotlib.pyplot as plt

If you've installed this module correctly, you can now use the following sample code to draw a plot in your terminal.

$ ipython
In [1]: import matplotlib
   ...: matplotlib.use('module://matplotlib-backend-sixel')
   ...: import numpy as np
   ...: import matplotlib.pyplot as plt
   ...: plt.style.use("dark_background")
   ...: t = np.linspace(0,5,200)
   ...: plt.fill_between(t,np.sin(t),np.cos(2*t),alpha=0.5)
   ...: plt.fill_between(t,np.cos(t),np.sin(2*t),alpha=0.5)
   ...: plt.show()

<plot is shown>

Example output using Gnome terminal compiled with SIXEL support

Example output

If you set your matplotlib to interactive mode via matplotlib.pyplot.ion() or by running python as python -i, non-empty figures are drawn on construction where possible. This allows you to use pandas' plot() calls directly, without calling plt.show(), and still enables you to manually construct and plt.show().

If your matplotlib is in non-interactive mode, you can construct your figures as usual, and then call plt.show() to render them to your terminal. This works from both a repl and when running scripts.

Internally, this backend is somewhat based on matplotlib's IPython support: it's a hybrid of image and GUI backend types. It works by using matplotlib's Agg backend to render the plot, and then calls imagemagick to convert to sixel format and then cat the image to your terminal. This means that plotting works as expected, but the image drawn to your terminal isn't interactive and animations aren't supported.