.. 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 :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 :download:`Download Python source code: colormap_normalizations_lognorm.py ` .. container:: sphx-glr-download :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 `_