testbed/matplotlib__matplotlib/galleries/examples/units/units_sample.py

"""
======================
Inches and Centimeters
======================

The example illustrates the ability to override default x and y units (ax1) to
inches and centimeters using the *xunits* and *yunits* parameters for the
`~.axes.Axes.plot` function. Note that conversions are applied to get numbers
to correct units.

.. only:: builder_html

   This example requires :download:`basic_units.py <basic_units.py>`

"""
from basic_units import cm, inch

import matplotlib.pyplot as plt
import numpy as np

cms = cm * np.arange(0, 10, 2)

fig, axs = plt.subplots(2, 2, layout='constrained')

axs[0, 0].plot(cms, cms)

axs[0, 1].plot(cms, cms, xunits=cm, yunits=inch)

axs[1, 0].plot(cms, cms, xunits=inch, yunits=cm)
axs[1, 0].set_xlim(-1, 4)  # scalars are interpreted in current units

axs[1, 1].plot(cms, cms, xunits=inch, yunits=inch)
axs[1, 1].set_xlim(3*cm, 6*cm)  # cm are converted to inches

plt.show()