René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"secondary_xaxis doesn't seem to use formatters","articleBody":"\u003c!--To help us understand and resolve your issue, please fill out the form to the best of your ability.--\u003e\r\n\u003c!--You can feel free to delete the sections that do not apply.--\u003e\r\n\r\n### Bug report\r\n\r\n`secondary_xaxis` (and `secondary_yaxis`?) doesn't seem to use formatters.\r\n\r\n**Code for reproduction**\r\n\r\n\u003c!--A minimum code snippet required to reproduce the bug.\r\nPlease make sure to minimize the number of dependencies required, and provide\r\nany necessary plotted data.\r\nAvoid using threads, as Matplotlib is (explicitly) not thread-safe.--\u003e\r\n\r\n```python\r\nimport matplotlib.pyplot as plt\r\nimport numpy as np\r\n\r\nfig, axs = plt.subplots(figsize=(0.6*4,0.6*3))\r\ny = np.random.rand(10)\r\nx = np.linspace(30,200,num=10)\r\n\r\np = plt.plot(x, y, marker='o', markersize=3)\r\nplt.xscale(\"log\")\r\n\r\ndef m2rho(m):\r\n    return 1 / m * 1000\r\n\r\ndef rho2m(rho):\r\n    return 1 / rho * 1000\r\n\r\nsecax = axs.secondary_xaxis('top', functions=(m2rho, rho2m))\r\n\r\nfrom matplotlib.ticker import ScalarFormatter, NullFormatter\r\nfor axis in [axs.xaxis, secax.xaxis]:\r\n    axis.set_major_formatter(ScalarFormatter())\r\n    axis.set_minor_formatter(NullFormatter())\r\naxs.set_xticks([50, 100, 200])\r\nsecax.set_xticks([20,10,5])\r\n\r\nplt.tight_layout()\r\nplt.show()\r\n```\r\n\r\n**Actual outcome**\r\n\r\n\u003c!--The output produced by the above code, which may be a screenshot, console output, etc.--\u003e\r\n\r\n![Figure_1](https://user-images.githubusercontent.com/12322814/68383153-66658a80-0155-11ea-85ab-79464b5b5848.png)\r\n\r\n**Expected outcome**\r\n\r\n\u003c!--A description of the expected outcome from the code snippet--\u003e\r\n\u003c!--If this used to work in an earlier version of Matplotlib, please note the version it used to work on--\u003e\r\n\r\nThe top axis should be formatted similarly to the bottom (first) x-axis. \r\n\r\n**Matplotlib version**\r\n\u003c!--Please specify your platform and versions of the relevant libraries you are using:--\u003e\r\n  * Operating system: Ubuntu 18.04\r\n  * Matplotlib version: 3.1.1\r\n  * Matplotlib backend: Qt5Agg\r\n  * Python version: 3.7.4\r\n\r\n\u003c!--Please tell us how you installed matplotlib and python e.g., from source, pip, conda--\u003e\r\n\u003c!--If you installed from conda, please specify which channel you used if not the default--\u003e\r\n\r\n","author":{"url":"https://github.com/fmikulasch","@type":"Person","name":"fmikulasch"},"datePublished":"2019-11-07T10:59:03.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":9},"url":"https://github.com/15621/matplotlib/issues/15621"}