.. DO NOT EDIT. .. THIS FILE WAS AUTOMATICALLY GENERATED BY SPHINX-GALLERY. .. TO MAKE CHANGES, EDIT THE SOURCE PYTHON FILE: .. "gallery/pyplots/axline.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_pyplots_axline.py: ============== Infinite lines ============== `~.axes.Axes.axvline` and `~.axes.Axes.axhline` draw infinite vertical / horizontal lines, at given *x* / *y* positions. They are usually used to mark special data values, e.g. in this example the center and limit values of the sigmoid function. `~.axes.Axes.axline` draws infinite straight lines in arbitrary directions. .. GENERATED FROM PYTHON SOURCE LINES 13-31 .. code-block:: Python import matplotlib.pyplot as plt import numpy as np t = np.linspace(-10, 10, 100) sig = 1 / (1 + np.exp(-t)) plt.axhline(y=0, color="black", linestyle="--") plt.axhline(y=0.5, color="black", linestyle=":") plt.axhline(y=1.0, color="black", linestyle="--") plt.axvline(color="grey") plt.axline((0, 0.5), slope=0.25, color="black", linestyle=(0, (5, 5))) plt.plot(t, sig, linewidth=2, label=r"$\sigma(t) = \frac{1}{1 + e^{-t}}$") plt.xlim(-10, 10) plt.xlabel("t") plt.legend(fontsize=14) plt.show() .. image-sg:: /gallery/pyplots/images/sphx_glr_axline_001.png :alt: axline :srcset: /gallery/pyplots/images/sphx_glr_axline_001.png, /gallery/pyplots/images/sphx_glr_axline_001_2_00x.png 2.00x :class: sphx-glr-single-img .. GENERATED FROM PYTHON SOURCE LINES 32-36 `~.axes.Axes.axline` can also be used with a ``transform`` parameter, which applies to the point, but not to the slope. This can be useful for drawing diagonal grid lines with a fixed slope, which stay in place when the plot limits are moved. .. GENERATED FROM PYTHON SOURCE LINES 36-44 .. code-block:: Python for pos in np.linspace(-2, 1, 10): plt.axline((pos, 0), slope=0.5, color='k', transform=plt.gca().transAxes) plt.ylim([0, 1]) plt.xlim([0, 1]) plt.show() .. image-sg:: /gallery/pyplots/images/sphx_glr_axline_002.png :alt: axline :srcset: /gallery/pyplots/images/sphx_glr_axline_002.png, /gallery/pyplots/images/sphx_glr_axline_002_2_00x.png 2.00x :class: sphx-glr-single-img .. GENERATED FROM PYTHON SOURCE LINES 45-53 .. admonition:: References The use of the following functions, methods, classes and modules is shown in this example: - `matplotlib.axes.Axes.axhline` / `matplotlib.pyplot.axhline` - `matplotlib.axes.Axes.axvline` / `matplotlib.pyplot.axvline` - `matplotlib.axes.Axes.axline` / `matplotlib.pyplot.axline` .. _sphx_glr_download_gallery_pyplots_axline.py: .. only:: html .. container:: sphx-glr-footer sphx-glr-footer-example .. container:: sphx-glr-download sphx-glr-download-jupyter :download:`Download Jupyter notebook: axline.ipynb ` .. container:: sphx-glr-download sphx-glr-download-python :download:`Download Python source code: axline.py ` .. only:: html .. rst-class:: sphx-glr-signature `Gallery generated by Sphinx-Gallery `_