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        "\n# Create boxes from error bars using PatchCollection\n\nIn this example, we snazz up a pretty standard error bar plot by adding\na rectangle patch defined by the limits of the bars in both the x- and\ny- directions. To do this, we have to write our own custom function\ncalled ``make_error_boxes``. Close inspection of this function will\nreveal the preferred pattern in writing functions for matplotlib:\n\n1. an `~.axes.Axes` object is passed directly to the function\n2. the function operates on the ``Axes`` methods directly, not through\n   the ``pyplot`` interface\n3. plotting keyword arguments that could be abbreviated are spelled out for\n   better code readability in the future (for example we use *facecolor*\n   instead of *fc*)\n4. the artists returned by the ``Axes`` plotting methods are then\n   returned by the function so that, if desired, their styles\n   can be modified later outside of the function (they are not\n   modified in this example).\n"
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      "source": [
        "import matplotlib.pyplot as plt\nimport numpy as np\n\nfrom matplotlib.collections import PatchCollection\nfrom matplotlib.patches import Rectangle\n\n# Number of data points\nn = 5\n\n# Dummy data\nnp.random.seed(19680801)\nx = np.arange(0, n, 1)\ny = np.random.rand(n) * 5.\n\n# Dummy errors (above and below)\nxerr = np.random.rand(2, n) + 0.1\nyerr = np.random.rand(2, n) + 0.2\n\n\ndef make_error_boxes(ax, xdata, ydata, xerror, yerror, facecolor='r',\n                     edgecolor='none', alpha=0.5):\n\n    # Loop over data points; create box from errors at each point\n    errorboxes = [Rectangle((x - xe[0], y - ye[0]), xe.sum(), ye.sum())\n                  for x, y, xe, ye in zip(xdata, ydata, xerror.T, yerror.T)]\n\n    # Create patch collection with specified colour/alpha\n    pc = PatchCollection(errorboxes, facecolor=facecolor, alpha=alpha,\n                         edgecolor=edgecolor)\n\n    # Add collection to Axes\n    ax.add_collection(pc)\n\n    # Plot errorbars\n    artists = ax.errorbar(xdata, ydata, xerr=xerror, yerr=yerror,\n                          fmt='none', ecolor='k')\n\n    return artists\n\n\n# Create figure and Axes\nfig, ax = plt.subplots(1)\n\n# Call function to create error boxes\n_ = make_error_boxes(ax, x, y, xerr, yerr)\n\nplt.show()"
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      "cell_type": "markdown",
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        ".. tags::\n\n   plot-type: errorbar\n   component: rectangle\n   component: patchcollection\n   domain: statistics\n\n.. 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.errorbar` / `matplotlib.pyplot.errorbar`\n   - `matplotlib.axes.Axes.add_collection`\n   - `matplotlib.collections.PatchCollection`\n\n"
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