View source for TUFLOW Viewer Matplotlib Font Error

This page describes how to fix TUFLOW Viewer if you get the following error (or similar). Unfortunately this is a bug with the plotting library TUFLOW Viewer uses (matplotlib) and is due to an issue with its cached data.
<pre>
ValueError: Failed to find font DejaVu Sans:style=normal:variant=normal:weight=normal:stretch=normal:size=10.0, and fallback to the default font was disabled
</pre>
To fix this issue, the matplotlib cache data will need to be deleted. The steps below describe how to do this:
<ol>
<li> Open QGIS
<li> Open the Python interpreter
: [[File: qgis_python_interpreter_tool_button.PNG]]
<li> In the python interpreter type the following commands:
<pre>
import matplotlib
print(matplotlib.get_cachedir())
</pre>
:[[File: qgis_python_interpreter_mpl_cache_location.PNG]]
<li> This will print the matplotlib cache directory
<li> In this directory, delete the fontlist-v330.json file
: [[File: file_explorer_mpl_cache_location.PNG]]
<li> Try opening TUFLOW Viewer (you should not need to restart QGIS, however if it still doesn't work then restarting QGIS will be worth trying)
<li> If the problem persists, try deleting all the fontlist files in the folder.
</ol>


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