.. DO NOT EDIT. .. THIS FILE WAS AUTOMATICALLY GENERATED BY SPHINX-GALLERY. .. TO MAKE CHANGES, EDIT THE SOURCE PYTHON FILE: .. "gallery/specialty_plots/hinton_demo.py" .. LINE NUMBERS ARE GIVEN BELOW. .. only:: html .. meta:: :keywords: codex .. note:: :class: sphx-glr-download-link-note :ref:`Go to the end ` to download the full example code .. rst-class:: sphx-glr-example-title .. _sphx_glr_gallery_specialty_plots_hinton_demo.py: =============== Hinton diagrams =============== Hinton diagrams are useful for visualizing the values of a 2D array (e.g. a weight matrix): Positive and negative values are represented by white and black squares, respectively, and the size of each square represents the magnitude of each value. Initial idea from David Warde-Farley on the SciPy Cookbook .. GENERATED FROM PYTHON SOURCE LINES 13-46 .. image-sg:: /gallery/specialty_plots/images/sphx_glr_hinton_demo_001.png :alt: hinton demo :srcset: /gallery/specialty_plots/images/sphx_glr_hinton_demo_001.png, /gallery/specialty_plots/images/sphx_glr_hinton_demo_001_2_00x.png 2.00x :class: sphx-glr-single-img .. code-block:: Python import matplotlib.pyplot as plt import numpy as np def hinton(matrix, max_weight=None, ax=None): """Draw Hinton diagram for visualizing a weight matrix.""" ax = ax if ax is not None else plt.gca() if not max_weight: max_weight = 2 ** np.ceil(np.log2(np.abs(matrix).max())) ax.patch.set_facecolor('gray') ax.set_aspect('equal', 'box') ax.xaxis.set_major_locator(plt.NullLocator()) ax.yaxis.set_major_locator(plt.NullLocator()) for (x, y), w in np.ndenumerate(matrix): color = 'white' if w > 0 else 'black' size = np.sqrt(abs(w) / max_weight) rect = plt.Rectangle([x - size / 2, y - size / 2], size, size, facecolor=color, edgecolor=color) ax.add_patch(rect) ax.autoscale_view() ax.invert_yaxis() if __name__ == '__main__': # Fixing random state for reproducibility np.random.seed(19680801) hinton(np.random.rand(20, 20) - 0.5) plt.show() .. _sphx_glr_download_gallery_specialty_plots_hinton_demo.py: .. only:: html .. container:: sphx-glr-footer sphx-glr-footer-example .. container:: sphx-glr-download sphx-glr-download-jupyter :download:`Download Jupyter notebook: hinton_demo.ipynb ` .. container:: sphx-glr-download sphx-glr-download-python :download:`Download Python source code: hinton_demo.py ` .. only:: html .. rst-class:: sphx-glr-signature `Gallery generated by Sphinx-Gallery `_