{ "cells": [ { "cell_type": "markdown", "metadata": {}, "source": [ "\n# Barcode\nThis demo shows how to produce a bar code.\n\nThe figure size is calculated so that the width in pixels is a multiple of the\nnumber of data points to prevent interpolation artifacts. Additionally, the\n``Axes`` is defined to span the whole figure and all ``Axis`` are turned off.\n\nThe data itself is rendered with `~.Axes.imshow` using\n\n- ``code.reshape(1, -1)`` to turn the data into a 2D array with one row.\n- ``imshow(..., aspect='auto')`` to allow for non-square pixels.\n- ``imshow(..., interpolation='nearest')`` to prevent blurred edges. This\n should not happen anyway because we fine-tuned the figure width in pixels,\n but just to be safe.\n" ] }, { "cell_type": "code", "execution_count": null, "metadata": { "collapsed": false }, "outputs": [], "source": [ "import matplotlib.pyplot as plt\nimport numpy as np\n\ncode = np.array([\n 1, 0, 1, 0, 1, 1, 1, 0, 1, 1, 0, 0, 0, 1, 0, 0, 1, 0, 1, 0, 0, 1, 1, 1,\n 0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 0, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 0,\n 1, 0, 1, 0, 0, 0, 0, 1, 0, 1, 1, 1, 0, 1, 0, 0, 1, 1, 0, 1, 1, 0, 0, 1,\n 1, 0, 0, 1, 1, 0, 1, 0, 1, 1, 1, 0, 0, 1, 0, 0, 0, 1, 0, 0, 1, 0, 1])\n\npixel_per_bar = 4\ndpi = 100\n\nfig = plt.figure(figsize=(len(code) * pixel_per_bar / dpi, 2), dpi=dpi)\nax = fig.add_axes([0, 0, 1, 1]) # span the whole figure\nax.set_axis_off()\nax.imshow(code.reshape(1, -1), cmap='binary', aspect='auto',\n interpolation='nearest')\nplt.show()" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ ".. admonition:: References\n\n The use of the following functions, methods, classes and modules is shown\n in this example:\n\n - `matplotlib.axes.Axes.imshow` / `matplotlib.pyplot.imshow`\n - `matplotlib.figure.Figure.add_axes`\n\n" ] } ], "metadata": { "kernelspec": { "display_name": "Python 3", "language": "python", "name": "python3" }, "language_info": { "codemirror_mode": { "name": "ipython", "version": 3 }, "file_extension": ".py", "mimetype": "text/x-python", "name": "python", "nbconvert_exporter": "python", "pygments_lexer": "ipython3", "version": "3.13.2" } }, "nbformat": 4, "nbformat_minor": 0 }