René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"ax.fill_between broken for log scale and values below zero","articleBody":"\r\n\r\n### ax.fill broken for log scale and values below zero\r\n\r\nWhen using ax.fill_between in log scale plots with y-values below zero, the result looks broken and areas are filled that should not be filled\r\n\r\n\r\n**Code for reproduction**\r\n\r\n\r\n```python\r\n\r\nimport numpy as np\r\nimport matplotlib.pyplot as plt\r\nxdata=np.arange(0,10,0.01)\r\nydata = np.exp(-xdata)\r\nedata = 0.2*(10-xdata)*np.cos(5*xdata)*np.exp(-xdata)\r\n\r\nfig, ax = plt.subplots()\r\nplt.yscale('log')\r\n\r\nax.fill_between(xdata, ydata - edata, ydata + edata)\r\n\r\nplt.savefig(\"test.png\")\r\n```\r\n\r\n**Actual outcome**\r\n\r\n![broken](https://user-images.githubusercontent.com/26244423/31670601-433a7536-b358-11e7-917c-cd12ce7484aa.png)\r\n\r\n**Expected outcome**\r\n\r\n![correct](https://user-images.githubusercontent.com/26244423/31670617-4a8b29b6-b358-11e7-82d6-c106a3429f54.png)\r\nThe correct example has been generated with matplotlib-2.0.2-1\r\n\r\n\r\nProbably related: #8623\r\nHow to deal with invalid values in log scale plots is certainly a matter of definition. However, it should never happen that areas are filled that should not be filled, as it is the case in the example above.\r\n\r\n**Matplotlib version**\r\n\r\n  * Operating system: arch linux\r\n  * Matplotlib version: 2.1.0-1\r\n  * Matplotlib backend: Qt5Agg\r\n  * Python version: 3.6.2\r\n  * Other libraries: numpy version: 1.13.3-1\r\n\r\nEverything installed using the package manager of arch linux.\r\n","author":{"url":"https://github.com/hsandmeyer","@type":"Person","name":"hsandmeyer"},"datePublished":"2017-10-17T14:55:26.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":2},"url":"https://github.com/9457/matplotlib/issues/9457"}