How to fix “could not find or load the Qt platform plugin windows” while using Matplotlib in PyCharm

Question

I am getting the error \"could not find or load the Qt platform plugin windows\" while using matplotlib in PyCharm.

How can I solve this?

Answer 1

I found that this was being caused by having the MiKTeX binaries in my PATH variable; and the wrong Qt dll's were being found. I just needed to re-arrange the PATH entries.

(Dependency Walker is such a useful tool.)

Answer 2

If you want to visualize your matplotlibs in an alternative way, use a different backend that generates the graphs, charts etc.

import matplotlib
matplotlib.use('TKAgg')

This worked for me.

Answer 3

Copy the folder

\Anaconda3\Library\plugins\platforms

to

\$\

where $ is your project interpreter folder. For example:

"\project\anaconda_env\Scripts\"

because PyCharm calls the python.exe in this folder, not the one in \Anaconda3.

Answer 4

I had the same issue with Qt 5.9 example btscanner.exe. What works in my case is:

1. Create a folder where is btscanner.exe ( my is c:\temp\BlueTouth )

2. Run from command prompt windeployqt.exe as follow: c:\qt\qt5.9.0\msvc2015\bin\windeployqt c:\temp\BlueTouth /* windeplyqt is the standard Qt tool to packet your application with any needed libraries or extra files and ready to deploy on other machine */

3. Result should be something like that:

C:\temp\BlueTouth\btscanner.exe 32 bit, release executable
Adding Qt5Svg for qsvgicon.dll
Skipping plugin qtvirtualkeyboardplugin.dll due to disabled dependencies.
Direct dependencies: Qt5Bluetooth Qt5Core Qt5Gui Qt5Widgets
All dependencies   : Qt5Bluetooth Qt5Core Qt5Gui Qt5Widgets
To be deployed     : Qt5Bluetooth Qt5Core Qt5Gui Qt5Svg Qt5Widgets
Warning: Cannot find Visual Studio installation directory, VCINSTALLDIR is not set.
Updating Qt5Bluetooth.dll.
Updating Qt5Core.dll.
Updating Qt5Gui.dll.
Updating Qt5Svg.dll.
Updating Qt5Widgets.dll.
Updating libGLESV2.dll.
Updating libEGL.dll.
Updating D3Dcompiler_47.dll.
Updating opengl32sw.dll.
Patching Qt5Core.dll...
Creating directory C:/temp/BlueTouth/iconengines.
Updating qsvgicon.dll.
Creating directory C:/temp/BlueTouth/imageformats.
Updating qgif.dll.
Updating qicns.dll.
Updating qico.dll.
Updating qjpeg.dll.
Updating qsvg.dll.
Updating qtga.dll.
Updating qtiff.dll.
Updating qwbmp.dll.
Updating qwebp.dll.
Creating directory C:/temp/BlueTouth/platforms.
Updating qwindows.dll.
Creating C:\temp\BlueTouth\translations...
Creating qt_bg.qm...
Creating qt_ca.qm...
Creating qt_cs.qm...
Creating qt_da.qm...
Creating qt_de.qm...
Creating qt_en.qm...
Creating qt_es.qm...
Creating qt_fi.qm...
Creating qt_fr.qm...
Creating qt_gd.qm...
Creating qt_he.qm...
Creating qt_hu.qm...
Creating qt_it.qm...
Creating qt_ja.qm...
Creating qt_ko.qm...
Creating qt_lv.qm...
Creating qt_pl.qm...
Creating qt_ru.qm...
Creating qt_sk.qm...
Creating qt_uk.qm...

4. If you take e look at c:\temp\BlueTouth folder will see the folders iconengines, imageformats, platforms, translations, and files D3Dcompiler_47.dll, libEGL.dll, libGLESV2.dll, opengl32sw.dll, Qt5Bluetouth.dll, Qt5Core.dll, Qt5Gui.dll, Qt5Svg.dll, Qt5Widgets.dll.

These are all of the files and folders need to run btscanner.exe on this or another machine. Just copy whole folder on other machine and run the file.

Answer 5

If you are running PyQt5 and PySide2, this solved the problem for me:

Copy the following files:

\Anaconda3\Lib\site-packages\PySide2\plugins\platforms\qminimal.dll
\Anaconda3\Lib\site-packages\PySide2\plugins\platforms\qoffscreen.dll
\Anaconda3\Lib\site-packages\PySide2\plugins\platforms\qwindows.dll

to:

\Anaconda3\Library\plugins\platforms\

Answer 6

Just add a system variable:

QT_QPA_PLATFORM_PLUGIN_PATH

and set its value to

C:\Python34\Lib\site-packages\PyQt4\plugins\platforms

Voilà. Done