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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"IndexError thrown by pyplot.legend() when plotting empty bar chart with label","articleBody":"### Bug report\r\n\r\n**Bug summary**\r\n\r\nWhen I try to create bar chart with no data, and add a label to this chart, IndexError will be raised when trying to create legend for this plot\r\n\r\n**Code for reproduction**\r\n\r\n```python\r\nimport matplotlib.pyplot as plt\r\nplt.bar([], [], label='foo')\r\nplt.legend()\r\n```\r\n\r\n**Actual outcome**\r\n\r\n```\r\nTraceback (most recent call last):\r\n  File \"test.py\", line 3, in \u003cmodule\u003e\r\n    plt.legend()\r\n  File \"/opt/conda/lib/python3.6/site-packages/matplotlib/pyplot.py\", line 3823, in legend\r\n    ret = gca().legend(*args, **kwargs)\r\n  File \"/opt/conda/lib/python3.6/site-packages/matplotlib/axes/_axes.py\", line 557, in legend\r\n    self.legend_ = mlegend.Legend(self, handles, labels, **kwargs)\r\n  File \"/opt/conda/lib/python3.6/site-packages/matplotlib/legend.py\", line 699, in __init__\r\n    self._init_legend_box(handles, labels, markerfirst)\r\n  File \"/opt/conda/lib/python3.6/site-packages/matplotlib/legend.py\", line 954, in _init_legend_box\r\n    fontsize, handlebox))\r\n  File \"/opt/conda/lib/python3.6/site-packages/matplotlib/legend_handler.py\", line 119, in legend_artist\r\n    fontsize, handlebox.get_transform())\r\n  File \"/opt/conda/lib/python3.6/site-packages/matplotlib/legend_handler.py\", line 303, in create_artists\r\n    self.update_prop(p, orig_handle, legend)\r\n  File \"/opt/conda/lib/python3.6/site-packages/matplotlib/legend_handler.py\", line 76, in update_prop\r\n    self._update_prop(legend_handle, orig_handle)\r\n  File \"/opt/conda/lib/python3.6/site-packages/matplotlib/legend_handler.py\", line 69, in _update_prop\r\n    self._update_prop_func(legend_handle, orig_handle)\r\n  File \"/opt/conda/lib/python3.6/site-packages/matplotlib/legend_handler.py\", line 42, in update_from_first_child\r\n    tgt.update_from(src.get_children()[0])\r\nIndexError: list index out of range\r\n```\r\n\r\n**Expected outcome**\r\n\r\n\u003c!--A description of the expected outcome from the code snippet--\u003e\r\n\u003c!--If this used to work in an earlier version of Matplotlib, please note the version it used to work on--\u003e\r\n\r\n**Matplotlib version**\r\n  * Operating system: Linux 1f8cb2653e0b 4.14.85-1-MANJARO #1 SMP PREEMPT Sat Dec 1 12:18:09 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux\r\n  * Matplotlib version: 3.0.2 (installed from PyPi)\r\n  * Matplotlib backend (`print(matplotlib.get_backend())`): module://backend_interagg\r\n  * Python version: 3.6.7\r\n\r\n\r\n","author":{"url":"https://github.com/VanDavv","@type":"Person","name":"VanDavv"},"datePublished":"2018-12-17T13:46:27.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":3},"url":"https://github.com/13003/matplotlib/issues/13003"}