{
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    {
      "cell_type": "markdown",
      "metadata": {},
      "source": [
        "\n# Fill the area between two vertical lines\n\nUsing `~.Axes.fill_betweenx` to color along the horizontal direction between\ntwo curves.\n"
      ]
    },
    {
      "cell_type": "code",
      "execution_count": null,
      "metadata": {
        "collapsed": false
      },
      "outputs": [],
      "source": [
        "import matplotlib.pyplot as plt\nimport numpy as np\n\ny = np.arange(0.0, 2, 0.01)\nx1 = np.sin(2 * np.pi * y)\nx2 = 1.2 * np.sin(4 * np.pi * y)\n\nfig, [ax1, ax2, ax3] = plt.subplots(1, 3, sharey=True, figsize=(6, 6))\n\nax1.fill_betweenx(y, 0, x1)\nax1.set_title('between (x1, 0)')\n\nax2.fill_betweenx(y, x1, 1)\nax2.set_title('between (x1, 1)')\nax2.set_xlabel('x')\n\nax3.fill_betweenx(y, x1, x2)\nax3.set_title('between (x1, x2)')"
      ]
    },
    {
      "cell_type": "markdown",
      "metadata": {},
      "source": [
        "Now fill between x1 and x2 where a logical condition is met. Note this is\ndifferent than calling::\n\n  fill_between(y[where], x1[where], x2[where])\n\nbecause of edge effects over multiple contiguous regions.\n\n"
      ]
    },
    {
      "cell_type": "code",
      "execution_count": null,
      "metadata": {
        "collapsed": false
      },
      "outputs": [],
      "source": [
        "fig, [ax, ax1] = plt.subplots(1, 2, sharey=True, figsize=(6, 6))\nax.plot(x1, y, x2, y, color='black')\nax.fill_betweenx(y, x1, x2, where=x2 >= x1, facecolor='green')\nax.fill_betweenx(y, x1, x2, where=x2 <= x1, facecolor='red')\nax.set_title('fill_betweenx where')\n\n# Test support for masked arrays.\nx2 = np.ma.masked_greater(x2, 1.0)\nax1.plot(x1, y, x2, y, color='black')\nax1.fill_betweenx(y, x1, x2, where=x2 >= x1, facecolor='green')\nax1.fill_betweenx(y, x1, x2, where=x2 <= x1, facecolor='red')\nax1.set_title('regions with x2 > 1 are masked')"
      ]
    },
    {
      "cell_type": "markdown",
      "metadata": {},
      "source": [
        "This example illustrates a problem; because of the data gridding, there are\nundesired unfilled triangles at the crossover points. A brute-force solution\nwould be to interpolate all arrays to a very fine grid before plotting.\n\n"
      ]
    },
    {
      "cell_type": "code",
      "execution_count": null,
      "metadata": {
        "collapsed": false
      },
      "outputs": [],
      "source": [
        "plt.show()"
      ]
    },
    {
      "cell_type": "markdown",
      "metadata": {},
      "source": [
        ".. tags::\n\n   plot-type: fill_between\n   level: beginner\n\n"
      ]
    }
  ],
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