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      "source": [
        "\n# Different scales on the same Axes\n\nDemo of how to display two scales on the left and right y-axis.\n\nThis example uses the Fahrenheit and Celsius scales.\n"
      ]
    },
    {
      "cell_type": "code",
      "execution_count": null,
      "metadata": {
        "collapsed": false
      },
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      "source": [
        "import matplotlib.pyplot as plt\nimport numpy as np\n\n\ndef fahrenheit2celsius(temp):\n    \"\"\"\n    Returns temperature in Celsius given Fahrenheit temperature.\n    \"\"\"\n    return (5. / 9.) * (temp - 32)\n\n\ndef make_plot():\n\n    # Define a closure function to register as a callback\n    def convert_ax_c_to_celsius(ax_f):\n        \"\"\"\n        Update second axis according to first axis.\n        \"\"\"\n        y1, y2 = ax_f.get_ylim()\n        ax_c.set_ylim(fahrenheit2celsius(y1), fahrenheit2celsius(y2))\n        ax_c.figure.canvas.draw()\n\n    fig, ax_f = plt.subplots()\n    ax_c = ax_f.twinx()\n\n    # automatically update ylim of ax2 when ylim of ax1 changes.\n    ax_f.callbacks.connect(\"ylim_changed\", convert_ax_c_to_celsius)\n    ax_f.plot(np.linspace(-40, 120, 100))\n    ax_f.set_xlim(0, 100)\n\n    ax_f.set_title('Two scales: Fahrenheit and Celsius')\n    ax_f.set_ylabel('Fahrenheit')\n    ax_c.set_ylabel('Celsius')\n\n    plt.show()\n\nmake_plot()"
      ]
    },
    {
      "cell_type": "markdown",
      "metadata": {},
      "source": [
        ".. tags::\n\n   component: axes\n   plot-type: line\n   level: beginner\n\n"
      ]
    }
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