.. _sphx_glr_gallery_scales_log_demo.py: ======== Log Demo ======== Examples of plots with logarithmic axes. .. image:: /gallery/scales/images/sphx_glr_log_demo_001.png :align: center .. code-block:: python import numpy as np import matplotlib.pyplot as plt # Data for plotting t = np.arange(0.01, 20.0, 0.01) # Create figure fig, ((ax1, ax2), (ax3, ax4)) = plt.subplots(2, 2) # log y axis ax1.semilogy(t, np.exp(-t / 5.0)) ax1.set(title='semilogy') ax1.grid() # log x axis ax2.semilogx(t, np.sin(2 * np.pi * t)) ax2.set(title='semilogx') ax2.grid() # log x and y axis ax3.loglog(t, 20 * np.exp(-t / 10.0), basex=2) ax3.set(title='loglog base 2 on x') ax3.grid() # With errorbars: clip non-positive values # Use new data for plotting x = 10.0**np.linspace(0.0, 2.0, 20) y = x**2.0 ax4.set_xscale("log", nonposx='clip') ax4.set_yscale("log", nonposy='clip') ax4.set(title='Errorbars go negative') ax4.errorbar(x, y, xerr=0.1 * x, yerr=5.0 + 0.75 * y) # ylim must be set after errorbar to allow errorbar to autoscale limits ax4.set_ylim(ymin=0.1) fig.tight_layout() plt.show() **Total running time of the script:** ( 0 minutes 0.455 seconds) .. only :: html .. container:: sphx-glr-footer .. container:: sphx-glr-download :download:`Download Python source code: log_demo.py ` .. container:: sphx-glr-download :download:`Download Jupyter notebook: log_demo.ipynb ` .. only:: html .. rst-class:: sphx-glr-signature `Gallery generated by Sphinx-Gallery `_