.. only:: html
.. note::
:class: sphx-glr-download-link-note
Click :ref:`here ` to download the full example code
.. rst-class:: sphx-glr-example-title
.. _sphx_glr_gallery_subplots_axes_and_figures_axes_margins.py:
======================================================
Controlling view limits using margins and sticky_edges
======================================================
The first figure in this example shows how to zoom in and out of a
plot using `~.Axes.margins` instead of `~.Axes.set_xlim` and
`~.Axes.set_ylim`. The second figure demonstrates the concept of
edge "stickiness" introduced by certain methods and artists and how
to effectively work around that.
.. code-block:: default
import numpy as np
import matplotlib.pyplot as plt
def f(t):
return np.exp(-t) * np.cos(2*np.pi*t)
t1 = np.arange(0.0, 3.0, 0.01)
ax1 = plt.subplot(212)
ax1.margins(0.05) # Default margin is 0.05, value 0 means fit
ax1.plot(t1, f(t1))
ax2 = plt.subplot(221)
ax2.margins(2, 2) # Values >0.0 zoom out
ax2.plot(t1, f(t1))
ax2.set_title('Zoomed out')
ax3 = plt.subplot(222)
ax3.margins(x=0, y=-0.25) # Values in (-0.5, 0.0) zooms in to center
ax3.plot(t1, f(t1))
ax3.set_title('Zoomed in')
plt.show()
.. image:: /gallery/subplots_axes_and_figures/images/sphx_glr_axes_margins_001.png
:alt: Zoomed out, Zoomed in
:class: sphx-glr-single-img
On the "stickiness" of certain plotting methods
"""""""""""""""""""""""""""""""""""""""""""""""
Some plotting functions make the axis limits "sticky" or immune to the will
of the `~.Axes.margins` methods. For instance, `~.Axes.imshow` and
`~.Axes.pcolor` expect the user to want the limits to be tight around the
pixels shown in the plot. If this behavior is not desired, you need to set
`~.Axes.use_sticky_edges` to `False`. Consider the following example:
.. code-block:: default
y, x = np.mgrid[:5, 1:6]
poly_coords = [
(0.25, 2.75), (3.25, 2.75),
(2.25, 0.75), (0.25, 0.75)
]
fig, (ax1, ax2) = plt.subplots(ncols=2)
# Here we set the stickiness of the axes object...
# ax1 we'll leave as the default, which uses sticky edges
# and we'll turn off stickiness for ax2
ax2.use_sticky_edges = False
for ax, status in zip((ax1, ax2), ('Is', 'Is Not')):
cells = ax.pcolor(x, y, x+y, cmap='inferno') # sticky
ax.add_patch(
plt.Polygon(poly_coords, color='forestgreen', alpha=0.5)
) # not sticky
ax.margins(x=0.1, y=0.05)
ax.set_aspect('equal')
ax.set_title('{} Sticky'.format(status))
plt.show()
.. image:: /gallery/subplots_axes_and_figures/images/sphx_glr_axes_margins_002.png
:alt: Is Sticky, Is Not Sticky
:class: sphx-glr-single-img
------------
References
""""""""""
The use of the following functions, methods is shown
in this example:
.. code-block:: default
import matplotlib
matplotlib.axes.Axes.margins
matplotlib.pyplot.margins
matplotlib.axes.Axes.use_sticky_edges
matplotlib.axes.Axes.pcolor
matplotlib.pyplot.pcolor
matplotlib.pyplot.Polygon
.. _sphx_glr_download_gallery_subplots_axes_and_figures_axes_margins.py:
.. only :: html
.. container:: sphx-glr-footer
:class: sphx-glr-footer-example
.. container:: sphx-glr-download sphx-glr-download-python
:download:`Download Python source code: axes_margins.py `
.. container:: sphx-glr-download sphx-glr-download-jupyter
:download:`Download Jupyter notebook: axes_margins.ipynb `
.. only:: html
.. rst-class:: sphx-glr-signature
Keywords: matplotlib code example, codex, python plot, pyplot
`Gallery generated by Sphinx-Gallery
`_