.. 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_userdemo_colormap_normalizations_lognorm.py:
===============================
Colormap Normalizations Lognorm
===============================
Demonstration of using norm to map colormaps onto data in non-linear ways.
.. image:: /gallery/userdemo/images/sphx_glr_colormap_normalizations_lognorm_001.png
:alt: colormap normalizations lognorm
:class: sphx-glr-single-img
.. code-block:: default
import numpy as np
import matplotlib.pyplot as plt
import matplotlib.colors as colors
'''
Lognorm: Instead of pcolor log10(Z1) you can have colorbars that have
the exponential labels using a norm.
'''
N = 100
X, Y = np.mgrid[-3:3:complex(0, N), -2:2:complex(0, N)]
# A low hump with a spike coming out of the top right. Needs to have
# z/colour axis on a log scale so we see both hump and spike. linear
# scale only shows the spike.
Z = np.exp(-X**2 - Y**2)
fig, ax = plt.subplots(2, 1)
pcm = ax[0].pcolor(X, Y, Z,
norm=colors.LogNorm(vmin=Z.min(), vmax=Z.max()),
cmap='PuBu_r')
fig.colorbar(pcm, ax=ax[0], extend='max')
pcm = ax[1].pcolor(X, Y, Z, cmap='PuBu_r')
fig.colorbar(pcm, ax=ax[1], extend='max')
plt.show()
.. _sphx_glr_download_gallery_userdemo_colormap_normalizations_lognorm.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: colormap_normalizations_lognorm.py `
.. container:: sphx-glr-download sphx-glr-download-jupyter
:download:`Download Jupyter notebook: colormap_normalizations_lognorm.ipynb `
.. only:: html
.. rst-class:: sphx-glr-signature
Keywords: matplotlib code example, codex, python plot, pyplot
`Gallery generated by Sphinx-Gallery
`_