.. 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_images_contours_and_fields_barcode_demo.py:
=======
Barcode
=======
This demo shows how to produce a bar code.
The figure size is calculated so that the width in pixels is a multiple of the
number of data points to prevent interpolation artifacts. Additionally, the
``Axes`` is defined to span the whole figure and all ``Axis`` are turned off.
The data itself is rendered with `~.Axes.imshow` using
- ``code.reshape(1, -1)`` to turn the data into a 2D array with one row.
- ``imshow(..., aspect='auto')`` to allow for non-square pixels.
- ``imshow(..., interpolation='nearest')`` to prevent blurred edges. This
should not happen anyway because we fine-tuned the figure width in pixels,
but just to be safe.
.. code-block:: default
import matplotlib.pyplot as plt
import numpy as np
code = np.array([
1, 0, 1, 0, 1, 1, 1, 0, 1, 1, 0, 0, 0, 1, 0, 0, 1, 0, 1, 0, 0, 1, 1, 1,
0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 0, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 0,
1, 0, 1, 0, 0, 0, 0, 1, 0, 1, 1, 1, 0, 1, 0, 0, 1, 1, 0, 1, 1, 0, 0, 1,
1, 0, 0, 1, 1, 0, 1, 0, 1, 1, 1, 0, 0, 1, 0, 0, 0, 1, 0, 0, 1, 0, 1])
pixel_per_bar = 4
dpi = 100
fig = plt.figure(figsize=(len(code) * pixel_per_bar / dpi, 2), dpi=dpi)
ax = fig.add_axes([0, 0, 1, 1]) # span the whole figure
ax.set_axis_off()
ax.imshow(code.reshape(1, -1), cmap='binary', aspect='auto',
interpolation='nearest')
plt.show()
.. image:: /gallery/images_contours_and_fields/images/sphx_glr_barcode_demo_001.png
:alt: barcode demo
:class: sphx-glr-single-img
------------
References
""""""""""
The use of the following functions, methods and classes is shown
in this example:
.. code-block:: default
import matplotlib
matplotlib.axes.Axes.imshow
matplotlib.pyplot.imshow
matplotlib.figure.Figure.add_axes
.. rst-class:: sphx-glr-script-out
Out:
.. code-block:: none
.. _sphx_glr_download_gallery_images_contours_and_fields_barcode_demo.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: barcode_demo.py `
.. container:: sphx-glr-download sphx-glr-download-jupyter
:download:`Download Jupyter notebook: barcode_demo.ipynb `
.. only:: html
.. rst-class:: sphx-glr-signature
Keywords: matplotlib code example, codex, python plot, pyplot
`Gallery generated by Sphinx-Gallery
`_