René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"linscalex/linscaley (for symlog) behaviour and documentation","articleBody":"According to [the documentation](https://matplotlib.org/devdocs/api/_as_gen/matplotlib.pyplot.yscale.html) linscalex/linscaley \"is the number of decades to use for each half of the linear range.\" This may be correct for base 10* (incidentally the documentation does not specify that this is the default base) but with a general base b it seems not to be, nor for a 'b-ade' as opposed to a decade. Also, there is a natural value log(e)/log(b) for this scaling (relative to the 'b-ade') which makes the scale continuous at the threshold and hence does not introduce gradient jumps in smooth curves. This may be a better default than 1.\r\n\r\n- See also issue #7008\r\n\r\n```python\r\nimport matplotlib.pyplot as plt\r\nimport numpy as np\r\n\r\nb = 2.  # Try 100. too\r\nt = 1.\r\n\r\n# Define some curves:\r\nx = np.linspace(0.1,3.,100)\r\ny1 = x\r\ny2 = x**2\r\ny3 = np.exp(x)/2.\r\ny4 = np.log(x)*2.\r\n\r\nplt.figure()\r\n\r\nplt.subplot(1,3,1)\r\nplt.title('base 10 default')\r\nplt.ylim(-100,100)\r\nplt.yscale('symlog',linthreshy=t)               # should set decade = half-linear\r\nplt.plot(x,y1)\r\nplt.plot(x,y2)\r\nplt.plot(x,y3)\r\nplt.plot(x,y4)\r\n\r\nplt.subplot(1,3,2)\r\nplt.title('base 10 smooth?')\r\nplt.ylim(-100,100)\r\nplt.yscale('symlog',linthreshy=t,linscaley=np.log10(np.e))      # smooth match?\r\nplt.plot(x,y1)\r\nplt.plot(x,y2)\r\nplt.plot(x,y3)\r\nplt.plot(x,y4)\r\n\r\nplt.subplot(1,3,3)\r\nplt.title('base %d default' % (b))\r\nplt.ylim(-100,100)\r\nplt.yscale('symlog',linthreshy=t,basey=b)       # doesn't set decade or b-ade = half-linear\r\nplt.plot(x,y1)\r\nplt.plot(x,y2)\r\nplt.plot(x,y3)\r\nplt.plot(x,y4)\r\n\r\nplt.show()\r\n```\r\nLinux; matplotlib 2.0.0, python 2.7.12 via conda\r\n\r\n*actually not; see below","author":{"url":"https://github.com/gregcolyer","@type":"Person","name":"gregcolyer"},"datePublished":"2018-02-02T12:10:56.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":8},"url":"https://github.com/10369/matplotlib/issues/10369"}