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        "\n# Affine transform of an image\n\n\nPrepending an affine transformation (`~.transforms.Affine2D`) to the `data\ntransform <data-coords>` of an image allows to manipulate the image's shape and\norientation.  This is an example of the concept of `transform chaining\n<transformation-pipeline>`.\n\nThe image of the output should have its boundary match the dashed yellow\nrectangle.\n"
      ]
    },
    {
      "cell_type": "code",
      "execution_count": null,
      "metadata": {
        "collapsed": false
      },
      "outputs": [],
      "source": [
        "import matplotlib.pyplot as plt\nimport numpy as np\n\nimport matplotlib.transforms as mtransforms\n\n\ndef get_image():\n    delta = 0.25\n    x = y = np.arange(-3.0, 3.0, delta)\n    X, Y = np.meshgrid(x, y)\n    Z1 = np.exp(-X**2 - Y**2)\n    Z2 = np.exp(-(X - 1)**2 - (Y - 1)**2)\n    Z = (Z1 - Z2)\n    return Z\n\n\ndef do_plot(ax, Z, transform):\n    im = ax.imshow(Z, interpolation='none',\n                   origin='lower',\n                   extent=[-2, 4, -3, 2], clip_on=True)\n\n    trans_data = transform + ax.transData\n    im.set_transform(trans_data)\n\n    # display intended extent of the image\n    x1, x2, y1, y2 = im.get_extent()\n    ax.plot([x1, x2, x2, x1, x1], [y1, y1, y2, y2, y1], \"y--\",\n            transform=trans_data)\n    ax.set_xlim(-5, 5)\n    ax.set_ylim(-4, 4)\n\n\n# prepare image and figure\nfig, ((ax1, ax2), (ax3, ax4)) = plt.subplots(2, 2)\nZ = get_image()\n\n# image rotation\ndo_plot(ax1, Z, mtransforms.Affine2D().rotate_deg(30))\n\n# image skew\ndo_plot(ax2, Z, mtransforms.Affine2D().skew_deg(30, 15))\n\n# scale and reflection\ndo_plot(ax3, Z, mtransforms.Affine2D().scale(-1, .5))\n\n# everything and a translation\ndo_plot(ax4, Z, mtransforms.Affine2D().\n        rotate_deg(30).skew_deg(30, 15).scale(-1, .5).translate(.5, -1))\n\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.transforms.Affine2D`\n\n"
      ]
    }
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