René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Axes.hist with log=True, histtype='step...' ignores bottom kwarg","articleBody":"The `Axes.hist` method doesn't handle the `bottom` kwarg properly when given `log=True` and `histtype='step'` or `histtype='stepfilled'`. As the example below shows, the method sets a `minimum` value to prevent issues with zeros on a log scale, but that supercedes a non-zero `bottom` kwarg:\n\n``` python\nimport numpy\nfrom matplotlib import pyplot\nfig = pyplot.figure()\nax = fig.gca()\nax.hist(numpy.random.random(1000), bins=100, log=True, bottom=1e-2, histtype='stepfilled')\nax.set_ylim(1e-2, 1e3)\nax.set_title('Bottom should be 1e-2, but instead is 1/base')\n```\n\n![mpl-hist-bottom](https://cloud.githubusercontent.com/assets/1618530/8580087/3562e70a-257e-11e5-89cf-63965212391c.png)\n\nI can correct the issue with the following edit:\n\n``` diff\ndiff --git a/lib/matplotlib/axes/_axes.py b/lib/matplotlib/axes/_axes.py\nindex 4d10e86..2392a6d 100644\n--- a/lib/matplotlib/axes/_axes.py\n+++ b/lib/matplotlib/axes/_axes.py\n@@ -5779,7 +5779,9 @@ class Axes(_AxesBase):\n                     logbase = self.yaxis._scale.base\n\n                 # Setting a minimum of 0 results in problems for log plots\n-                if normed or weights is not None:\n+                if np.min(bottom) \u003e 0:\n+                    minimum = np.min(bottom)\n+                elif normed or weights is not None:\n                     # For normed data, set to log base * minimum data value\n                     # (gives 1 full tick-label unit for the lowest filled bin)\n                     ndata = np.array(n)\n```\n\nwhich uses the `bottom` value to set the `minimum` if it's nonzero. If this is confirmed as a bug, I can open a PR.\n","author":{"url":"https://github.com/duncanmmacleod","@type":"Person","name":"duncanmmacleod"},"datePublished":"2015-07-08T19:39:09.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":1},"url":"https://github.com/4606/matplotlib/issues/4606"}