René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"2.1 change - Axis Limit Error ","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**The new feature of raising exceptions for invalid limits and related changes seem to break code**\r\n\r\n\u003c!--A short 1-2 sentences that succinctly describes the bug--\u003e\r\n\r\n**Some new features in dealing with limits seem to break plotting, when using very small values (or NaN).  I was not able to track down what is all broken, may be one than just one isolated change ... this worked smoothly in 2.0.2**\r\n\r\n\u003c!--A minimum code snippet required to reproduce the bug, also minimizing the number of dependencies required--\u003e\r\n\r\n```python3\r\nimport numpy as np\r\nfrom matplotlib.pyplot import *\r\nx = np.arange(-1000,10,1)\r\ny = 10.**x\r\nplot(x,y)\r\nyscale('log')\r\nylim(1e-10, 1e10)\r\nshow()\r\n```\r\n\u003c!--The output produced by the above code, which may be a screenshot, console output, etc.--\u003e\r\n\r\nif you now zoom out in \"pan\" mode eventually you run into error messages of the kind\r\n\r\n```\r\nValueError: Axis limits cannot be NaN or Inf\r\nTraceback (most recent call last):\r\n  File \"/home/alex/Python/lib/python3.6/site-packages/matplotlib/cbook/__init__.py\", line 389, in process\r\n    proxy(*args, **kwargs)\r\n  File \"/home/alex/Python/lib/python3.6/site-packages/matplotlib/cbook/__init__.py\", line 227, in __call__\r\n    return mtd(*args, **kwargs)\r\n  File \"/home/alex/Python/lib/python3.6/site-packages/matplotlib/backend_bases.py\", line 3056, in drag_pan\r\n    a.drag_pan(self._button_pressed, event.key, event.x, event.y)\r\n  File \"/home/alex/Python/lib/python3.6/site-packages/matplotlib/axes/_base.py\", line 3837, in drag_pan\r\n    self.set_ylim(*result.intervaly)\r\n  File \"/home/alex/Python/lib/python3.6/site-packages/matplotlib/axes/_base.py\", line 3226, in set_ylim\r\n    top = self._validate_converted_limits(top, self.convert_yunits)\r\n  File \"/home/alex/Python/lib/python3.6/site-packages/matplotlib/axes/_base.py\", line 2836, in _validate_converted_limits\r\n    raise ValueError(\"Axis limits cannot be NaN or Inf\")\r\nValueError: Axis limits cannot be NaN or Inf\r\n```\r\nand it all get very slow, I see the `hour glass`  cursor for a line with 1000 points.\r\n\r\nIf you have a more complex plot with anything after this error these parts may be missing.  Plot limits for axis get mutilated as well.  I have also seen cases where `home` button no longer gets you back to the original limits ...   For example, try to bus down really, really far (below 1e-300).  After doing that, press `home`.  For my test case,  this showed me limits somewhere from 1e-50 to 1e+38.  (in mpl 2.0.2 this does not happen)\r\n\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\nIn Maplotlib 2.0.2, no error occurs, all runs smoothly.  Values below threshold are truncated.  Many of the plots I had are completely mutilated in this new version, I do not even know where I can start to look for a fix, as the errors do not point to any part of my code, nor is there an error raised in interactive mode  where I could debug it.  So it is not clear to me how I can help to find the problem in Matplotlib, or adjust my code from a 2.0.2-compatible version to one that works with 2.1.0.\r\n\r\n(In 2.0.2 I only see a message as below.) \r\n```\r\n/home/alex/Python/lib/python3.6/site-packages/matplotlib/ticker.py:1076: RuntimeWarning: divide by zero encountered in double_scalars\r\n  coeff = np.round(x / b ** exponent)\r\n```\r\n\r\n**proposed fix**\r\n\r\nplease revert to previous way of handling limits etc.\r\n\r\nI assume this is related to \r\n```\r\nInvalid (Non-finite) Axis Limit Error\r\nWhen using set_xlim() and set_ylim(), passing non-finite values now results in a ValueError. The previous behavior resulted in the limits being erroneously reset to (-0.001, 0.001).\r\n```\r\nfrom \r\nhttp://matplotlib.org/api/api_changes.html#api-changes-in-2-1-0\r\nspecifically\r\nhttp://matplotlib.org/api/api_changes.html#invalid-non-finite-axis-limit-error\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:  Fedora 26, 64bit\r\n  * Matplotlib version: 2.1\r\n  * Matplotlib backend (`print(matplotlib.get_backend())`): TkAgg\r\n  * Python version: 3.6.3\r\n  * Jupyter version (if applicable): N/A\r\n  * Other libraries: numpy 1.13.3\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\npip3","author":{"url":"https://github.com/2sn","@type":"Person","name":"2sn"},"datePublished":"2017-10-11T06:04:55.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":3},"url":"https://github.com/9361/matplotlib/issues/9361"}