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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Scatter3D: facecolor or color to \"none\" leads to an error","articleBody":"Assigning \"none\" to facecolor or color parameter does not work any longer for 3D scatter plots. My current version of matplotlib is 3.2.2\r\n\r\n```python\r\nimport numpy as np\r\nimport matplotlib.pyplot as plt\r\nfrom mpl_toolkits.mplot3d import Axes3D\r\n\r\nnp.random.seed(2121)\r\nx = np.random.randn(3, 10)\r\n\r\n# %% 2D (still working)\r\nfig = plt.figure()\r\nax = fig.add_subplot(111)\r\nax.scatter(*x[0:2, :], marker='o', facecolor='blue', color='red', s=50)  # working\r\nfig = plt.figure()\r\nax = fig.add_subplot(111)\r\nax.scatter(*x[0:2, :], marker='o', facecolor='none', color='red', s=50)   # working\r\nfig = plt.figure()\r\nax = fig.add_subplot(111)\r\nax.scatter(*x[0:2, :], marker='o', facecolor='blue', color='none', s=50)   # working\r\n\r\n# %% 3D (not working any longer)\r\nfig = plt.figure()\r\nax = fig.add_subplot(111, projection='3d')\r\nax.scatter(*x, marker='o', facecolor='blue', color='red', s=50)   # working\r\nfig = plt.figure()\r\nax = fig.add_subplot(111, projection='3d')\r\nax.scatter(*x, marker='o', facecolor=\"none\", color='red', s=50)   # NOT working\r\nfig = plt.figure()\r\nax = fig.add_subplot(111, projection='3d')\r\nax.scatter(*x, marker='o', facecolor='blue', color=\"none\", s=50)  # NOT working\r\n```\r\n\r\nThe console returns the following error:\r\n```\r\n\u003cmpl_toolkits.mplot3d.art3d.Path3DCollection at 0x7f668ea53b90\u003eTraceback (most recent call last):\r\n  File \"/home/vanwynch/anaconda3/lib/python3.7/site-packages/matplotlib/backends/backend_qt5.py\", line 496, in _draw_idle\r\n    self.draw()\r\n  File \"/home/vanwynch/anaconda3/lib/python3.7/site-packages/matplotlib/backends/backend_agg.py\", line 393, in draw\r\n    self.figure.draw(self.renderer)\r\n  File \"/home/vanwynch/anaconda3/lib/python3.7/site-packages/matplotlib/artist.py\", line 38, in draw_wrapper\r\n    return draw(artist, renderer, *args, **kwargs)\r\n  File \"/home/vanwynch/anaconda3/lib/python3.7/site-packages/matplotlib/figure.py\", line 1736, in draw\r\n    renderer, self, artists, self.suppressComposite)\r\n  File \"/home/vanwynch/anaconda3/lib/python3.7/site-packages/matplotlib/image.py\", line 137, in _draw_list_compositing_images\r\n    a.draw(renderer)\r\n  File \"/home/vanwynch/anaconda3/lib/python3.7/site-packages/matplotlib/artist.py\", line 38, in draw_wrapper\r\n    return draw(artist, renderer, *args, **kwargs)\r\n  File \"/home/vanwynch/anaconda3/lib/python3.7/site-packages/mpl_toolkits/mplot3d/axes3d.py\", line 293, in draw\r\n    reverse=True)):\r\n  File \"/home/vanwynch/anaconda3/lib/python3.7/site-packages/mpl_toolkits/mplot3d/axes3d.py\", line 292, in \u003clambda\u003e\r\n    key=lambda col: col.do_3d_projection(renderer),\r\n  File \"/home/vanwynch/anaconda3/lib/python3.7/site-packages/mpl_toolkits/mplot3d/art3d.py\", line 540, in do_3d_projection\r\n    fcs = (_zalpha(self._facecolor3d, vzs) if self._depthshade else\r\n  File \"/home/vanwynch/anaconda3/lib/python3.7/site-packages/mpl_toolkits/mplot3d/art3d.py\", line 847, in _zalpha\r\n    rgba = np.broadcast_to(mcolors.to_rgba_array(colors), (len(zs), 4))\r\n  File \"\u003c__array_function__ internals\u003e\", line 6, in broadcast_to\r\n  File \"/home/vanwynch/anaconda3/lib/python3.7/site-packages/numpy/lib/stride_tricks.py\", line 182, in broadcast_to\r\n    return _broadcast_to(array, shape, subok=subok, readonly=True)\r\n  File \"/home/vanwynch/anaconda3/lib/python3.7/site-packages/numpy/lib/stride_tricks.py\", line 127, in _broadcast_to\r\n    op_flags=['readonly'], itershape=shape, order='C')\r\nValueError: operands could not be broadcast together with remapped shapes [original-\u003eremapped]: (0,4) and requested shape (10,4)\r\nTraceback (most recent call last):\r\n  File \"/home/vanwynch/anaconda3/lib/python3.7/site-packages/matplotlib/backends/backend_qt5.py\", line 496, in _draw_idle\r\n    self.draw()\r\n  File \"/home/vanwynch/anaconda3/lib/python3.7/site-packages/matplotlib/backends/backend_agg.py\", line 393, in draw\r\n    self.figure.draw(self.renderer)\r\n  File \"/home/vanwynch/anaconda3/lib/python3.7/site-packages/matplotlib/artist.py\", line 38, in draw_wrapper\r\n    return draw(artist, renderer, *args, **kwargs)\r\n  File \"/home/vanwynch/anaconda3/lib/python3.7/site-packages/matplotlib/figure.py\", line 1736, in draw\r\n    renderer, self, artists, self.suppressComposite)\r\n  File \"/home/vanwynch/anaconda3/lib/python3.7/site-packages/matplotlib/image.py\", line 137, in _draw_list_compositing_images\r\n    a.draw(renderer)\r\n  File \"/home/vanwynch/anaconda3/lib/python3.7/site-packages/matplotlib/artist.py\", line 38, in draw_wrapper\r\n    return draw(artist, renderer, *args, **kwargs)\r\n  File \"/home/vanwynch/anaconda3/lib/python3.7/site-packages/mpl_toolkits/mplot3d/axes3d.py\", line 293, in draw\r\n    reverse=True)):\r\n  File \"/home/vanwynch/anaconda3/lib/python3.7/site-packages/mpl_toolkits/mplot3d/axes3d.py\", line 292, in \u003clambda\u003e\r\n    key=lambda col: col.do_3d_projection(renderer),\r\n  File \"/home/vanwynch/anaconda3/lib/python3.7/site-packages/mpl_toolkits/mplot3d/art3d.py\", line 540, in do_3d_projection\r\n    fcs = (_zalpha(self._facecolor3d, vzs) if self._depthshade else\r\n  File \"/home/vanwynch/anaconda3/lib/python3.7/site-packages/mpl_toolkits/mplot3d/art3d.py\", line 847, in _zalpha\r\n    rgba = np.broadcast_to(mcolors.to_rgba_array(colors), (len(zs), 4))\r\n  File \"\u003c__array_function__ internals\u003e\", line 6, in broadcast_to\r\n  File \"/home/vanwynch/anaconda3/lib/python3.7/site-packages/numpy/lib/stride_tricks.py\", line 182, in broadcast_to\r\n    return _broadcast_to(array, shape, subok=subok, readonly=True)\r\n  File \"/home/vanwynch/anaconda3/lib/python3.7/site-packages/numpy/lib/stride_tricks.py\", line 127, in _broadcast_to\r\n    op_flags=['readonly'], itershape=shape, order='C')\r\nValueError: operands could not be broadcast together with remapped shapes [original-\u003eremapped]: (0,4) and requested shape (10,4)\r\n```\r\n\r\nThe workaround is to use (0, 0, 0, 0) as color/facecolor rather than \"none\" :\r\n```python\r\n# %% 3D workaround\r\nfig = plt.figure()\r\nax = fig.add_subplot(111, projection='3d')\r\nax.scatter(*x, marker='o', facecolor='blue', color='red', s=50)   # working\r\nfig = plt.figure()\r\nax = fig.add_subplot(111, projection='3d')\r\nax.scatter(*x, marker='o', facecolor=(0, 0, 0, 0), color='red', s=50)   # working\r\nfig = plt.figure()\r\nax = fig.add_subplot(111, projection='3d')\r\nax.scatter(*x, marker='o', facecolor='blue', color=(0, 0, 0, 0), s=50)   # working\r\n```","author":{"url":"https://github.com/cvanwynsberghe","@type":"Person","name":"cvanwynsberghe"},"datePublished":"2020-07-22T16:53:59.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":6},"url":"https://github.com/18020/matplotlib/issues/18020"}