René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"imshow(..., alpha=0.5) produces different results in 2.x","articleBody":"I think I have whittled this down sufficiently from the Cartopy example that is failing. Running `imshow(..., alpha=0.5)` produces a different result in 2.0.0b1 vs. 1.5.1 (both installed via conda.)\n\n``` python\nimport numpy as np\nimport matplotlib.pyplot as plt\nimport matplotlib as mpl\n\n# mpl.style.use('classic')\n\nim = np.zeros((100, 100, 3), dtype=np.uint8)\nplt.imshow(im, extent=(1, 10, 1, 10), alpha=0.5)\nplt.xlim(0, 11)\nplt.ylim(0, 11)\n\nplt.savefig('imshow_alpha.png')\n```\n\nUsing 1.5.1:\n![imshow_alpha_1 5 1](https://cloud.githubusercontent.com/assets/302469/15812915/443b626e-2b88-11e6-89ca-14c0afbf4648.png)\nUsing 2.0.0b1:\n![imshow_alpha_2 0](https://cloud.githubusercontent.com/assets/302469/15812917/4d8bc746-2b88-11e6-8e9f-68a37cd456d6.png)\nUsing 2.0.0b1 with the classic style:\n![imshow_alpha_2 0_classic](https://cloud.githubusercontent.com/assets/302469/15812919/543d038e-2b88-11e6-9607-e80ae97955f6.png)\n\nGIMP tells me that the first is 50%, while the latter two are 75%.\n","author":{"url":"https://github.com/QuLogic","@type":"Person","name":"QuLogic"},"datePublished":"2016-06-06T05:47:18.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":4},"url":"https://github.com/6540/matplotlib/issues/6540"}