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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Linewidth(s) keywords not working with quiver","articleBody":"### Cannot set different arrow sizes using quiver\r\n\r\n**This seems to be a regression in the behaviour of the quiver function**\r\n\r\nAccording to [this SO post](http://stackoverflow.com/questions/15701952/change-size-of-arrows-using-matplotlib-quiver#15702208), ``quiver`` used to accept a `linewidths` array argument to set the arrow sizes; however, this is no longer true with 2.02 on Py2/3K.\r\nThe `linewidth` item pops 5 times in [`quiver.py`](https://github.com/matplotlib/matplotlib/blob/master/lib/matplotlib/quiver.py) though.\r\n\r\n**Code for reproduction**\r\nFrom the [SO post](http://stackoverflow.com/questions/15701952/change-size-of-arrows-using-matplotlib-quiver#15702208), but the code (reported as working) does not work on my install.\r\n\r\n```python\r\nimport matplotlib.pyplot as plt\r\nimport numpy as np\r\nsin = np.sin\r\ncos = np.cos\r\n\r\n# http://stackoverflow.com/questions/6370742/#6372413\r\nxmax = 4.0\r\nxmin = -xmax\r\nD = 20\r\nymax = 4.0\r\nymin = -ymax\r\nx = np.linspace(xmin, xmax, D)\r\ny = np.linspace(ymin, ymax, D)\r\nX, Y = np.meshgrid(x, y)\r\n# plots the vector field for Y'=Y**3-3*Y-X\r\ndeg = np.arctan(Y ** 3 - 3 * Y - X)\r\nwidths = np.linspace(0, 2, X.size)\r\nplt.quiver(X, Y, cos(deg), sin(deg), linewidths=widths)\r\nplt.show()\r\n```\r\n\r\n**Actual outcome**\r\n\r\nOutput is the same as that of the initial [SO post](http://stackoverflow.com/questions/6370742/#6372413) where the `linewidths` keyword is not set.\r\n\r\n**Matplotlib version**\r\n\r\n  * Operating System: Manjaro\r\n  * Matplotlib Version: 2.02\r\n  * Python Version: 2.7.13 \u0026 3.6.1\r\n  * Jupyter Version (if applicable): /\r\n  * Other Libraries: numpy 1.12.1","author":{"url":"https://github.com/Silmathoron","@type":"Person","name":"Silmathoron"},"datePublished":"2017-05-16T08:06:39.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":6},"url":"https://github.com/8630/matplotlib/issues/8630"}