Hi people, I’m in Plasma 6 + wayland setup. When I try to plot using matplotlib in virtuelenv with files below, I got test.py:15: UserWarning: FigureCanvasAgg is non-interactive, and thus cannot be shown plt.show(). I’ve run out of ideas about how to fix this error. Any new perspective?
The Flake
{
description = "Debug Matplotlib";
inputs = {
nixpkgs.url = "nixpkgs/nixos-24.05";
flake-utils.url = "github:numtide/flake-utils";
};
outputs = {
nixpkgs,
flake-utils,
...
}:
flake-utils.lib.eachDefaultSystem (system: let
pkgs = nixpkgs.legacyPackages.${system};
buildInputs = [
(pkgs.python3.withPackages (python-pkgs: [
python-pkgs.pip
python-pkgs.virtualenv
]))
];
in {
devShells.default = pkgs.mkShell {
inherit buildInputs;
shellHook = ''
export LD_LIBRARY_PATH="${pkgs.stdenv.cc.cc.lib}/lib/:$LD_LIBRARY_PATH"
export LD_LIBRARY_PATH="${pkgs.lib.makeLibraryPath buildInputs}:$LD_LIBRARY_PATH"
source .venv/bin/activate
'';
};
devShells.setupShell = pkgs.mkShell {
inherit buildInputs;
shellHook = ''
export LD_LIBRARY_PATH=${pkgs.stdenv.cc.cc.lib}/lib/
rm -rf .venv
virtualenv --no-setuptools .venv
source .venv/bin/activate
pip install -r requirements.txt
'';
};
});
}
The requirement.txt
matplotlib
PyQt6
The test.py
import matplotlib.pyplot as plt
import numpy as np
# Data for plotting
t = np.arange(0.0, 2.0, 0.01)
s = 1 + np.sin(2 * np.pi * t)
fig, ax = plt.subplots()
ax.plot(t, s)
ax.set(xlabel='time (s)', ylabel='voltage (mV)',
title='About as simple as it gets, folks')
ax.grid()
plt.show()
Edit: when I put matplotlib.use('QtAgg') in test.py I got
ImportError: Failed to import any of the following Qt binding modules: PyQt6, PySide6, PyQt5, PySide2
Wierd, my pip list shows
contourpy 1.3.0
cycler 0.12.1
fonttools 4.53.1
kiwisolver 1.4.7
matplotlib 3.9.2
numpy 2.1.1
packaging 24.1
pillow 10.4.0
pip 24.2
pyparsing 3.1.4
PyQt6 6.7.1
PyQt6-Qt6 6.7.2
PyQt6_sip 13.8.0
python-dateutil 2.9.0.post0
six 1.16.0
wheel 0.44.0
Edit 2: When I run import PyQt6.QtCore in this environment, I got
ImportError: libglib-2.0.so.0: cannot open shared object file: No such file or directory