ImportError: Failed to import any of the following Qt binding modules: PyQt5, PySide2

[adthoms]

Following the current installation guide, the following errors are reproduced when running:

python3 hat_experiments.py:

Traceback (most recent call last):
  File "/home/alex/catkin_ws/src/cora-experiments/experiments/hat_experiments.py", line 2, in <module>
    from py_factor_graph.io.pyfg_text import read_from_pyfg_text
  File "/home/alex/catkin_ws/src/PyFactorGraph/py_factor_graph/io/pyfg_text.py", line 3, in <module>
    from py_factor_graph.factor_graph import FactorGraphData
  File "/home/alex/catkin_ws/src/PyFactorGraph/py_factor_graph/factor_graph.py", line 51, in <module>
    from py_factor_graph.utils.plot_utils import (
  File "/home/alex/catkin_ws/src/PyFactorGraph/py_factor_graph/utils/plot_utils.py", line 11, in <module>
    from evo.tools import file_interface, plot as evoplot
  File "/home/alex/anaconda3/envs/cora/lib/python3.10/site-packages/evo/tools/plot.py", line 33, in <module>
    mpl.use(SETTINGS.plot_backend)
  File "/home/alex/anaconda3/envs/cora/lib/python3.10/site-packages/matplotlib/__init__.py", line 1249, in use
    plt.switch_backend(name)
  File "/home/alex/anaconda3/envs/cora/lib/python3.10/site-packages/matplotlib/pyplot.py", line 342, in switch_backend
    module = importlib.import_module(cbook._backend_module_name(newbackend))
  File "/home/alex/anaconda3/envs/cora/lib/python3.10/importlib/__init__.py", line 126, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "/home/alex/anaconda3/envs/cora/lib/python3.10/site-packages/matplotlib/backends/backend_qt5agg.py", line 7, in <module>
    from .backend_qtagg import (    # noqa: F401, E402 # pylint: disable=W0611
  File "/home/alex/anaconda3/envs/cora/lib/python3.10/site-packages/matplotlib/backends/backend_qtagg.py", line 9, in <module>
    from .qt_compat import QT_API, QtCore, QtGui
  File "/home/alex/anaconda3/envs/cora/lib/python3.10/site-packages/matplotlib/backends/qt_compat.py", line 133, in <module>
    raise ImportError(
ImportError: Failed to import any of the following Qt binding modules: PyQt5, PySide2

python3 tiers_experiments.py:

Traceback (most recent call last):
  File "/home/alex/catkin_ws/src/cora-experiments/experiments/tiers_experiments.py", line 1, in <module>
    from py_factor_graph.io.pyfg_text import read_from_pyfg_text
  File "/home/alex/catkin_ws/src/PyFactorGraph/py_factor_graph/io/pyfg_text.py", line 3, in <module>
    from py_factor_graph.factor_graph import FactorGraphData
  File "/home/alex/catkin_ws/src/PyFactorGraph/py_factor_graph/factor_graph.py", line 51, in <module>
    from py_factor_graph.utils.plot_utils import (
  File "/home/alex/catkin_ws/src/PyFactorGraph/py_factor_graph/utils/plot_utils.py", line 11, in <module>
    from evo.tools import file_interface, plot as evoplot
  File "/home/alex/anaconda3/envs/cora/lib/python3.10/site-packages/evo/tools/plot.py", line 33, in <module>
    mpl.use(SETTINGS.plot_backend)
  File "/home/alex/anaconda3/envs/cora/lib/python3.10/site-packages/matplotlib/__init__.py", line 1249, in use
    plt.switch_backend(name)
  File "/home/alex/anaconda3/envs/cora/lib/python3.10/site-packages/matplotlib/pyplot.py", line 342, in switch_backend
    module = importlib.import_module(cbook._backend_module_name(newbackend))
  File "/home/alex/anaconda3/envs/cora/lib/python3.10/importlib/__init__.py", line 126, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "/home/alex/anaconda3/envs/cora/lib/python3.10/site-packages/matplotlib/backends/backend_qt5agg.py", line 7, in <module>
    from .backend_qtagg import (    # noqa: F401, E402 # pylint: disable=W0611
  File "/home/alex/anaconda3/envs/cora/lib/python3.10/site-packages/matplotlib/backends/backend_qtagg.py", line 9, in <module>
    from .qt_compat import QT_API, QtCore, QtGui
  File "/home/alex/anaconda3/envs/cora/lib/python3.10/site-packages/matplotlib/backends/qt_compat.py", line 133, in <module>
    raise ImportError(
ImportError: Failed to import any of the following Qt binding modules: PyQt5, PySide2

single_drone_experiments.py:

[pyfg_text.py:686] py_factor_graph.utils.logging_utils INFO - Loaded factor graph in PyFG text format from /home/alex/catkin_ws/src/cora-experiments/data/single_drone/factor_graph.pyfg
Reading data from /home/alex/catkin_ws/src/cora-experiments/data/single_drone/factor_graph.pyfg
Finished loading data in 1.305308 seconds.
Manopt settings:
 Solver verbosity: 0
 Initialization strategy: random
 Setting stopping tolerance for norm of Riemannian gradient to: 0.001 [default]
 Setting stopping tolerance for relative function decrease to: 1e-05 [default]
 Setting maximum number of Hessian-vector products to evaluate in each truncated Newton iteration to: 300 [default]
 Setting minimum number of trust-region iterations to: 1 [default]
 Setting maximum number of trust-region iterations to: 100 [default]

Solving Riemannian optimization problems using Manopt's "trustregions" solver

Setting up preconditioner...
Warning: No valid initialization given. Using random point as default.
> In cora (line 52)
In cora_python_interface (line 40)
Trying to solve at rank 3
Trying to solve at rank 4
Trying to solve at rank 5
Solution certified with certEpsilon = 4.010953e-06 
The staircase algorithm has found an optimal solution with dimension 5 and cost 4.010953.
Singular values of lifted solution are: [51.8178086219621;47.0618163433195;41.8810223594389;19.0275923098514;0.175639129004057] 
Refined cost is 4.095614
Warning: Gap: 8.466121e-02 Rel Gap: 2.110751e+00
> In cora (line 119)
In cora_python_interface (line 40)
Warning: Gap between final solution and optimal solution is 0.084661
> In cora (line 125)
In cora_python_interface (line 40)
Warning: Relative suboptimality is 2.110751%
> In cora (line 126)
In cora_python_interface (line 40)
Results saved to /home/alex/catkin_ws/src/cora-experiments/data/single_drone/factor_graph_results.mat
CORA iterates info saved to /home/alex/catkin_ws/src/cora-experiments/data/single_drone/factor_graph_cora_iterates_info.mat
Warning: Function does not currently correctly handle priors!!
> In write_result_to_tum (line 14)
In cora_python_interface (line 54)
Warning: Assuming no priors - get_robot t_idxs
> In get_robot_t_idxs (line 4)
In write_result_to_tum (line 37)
In cora_python_interface (line 54)
Warning: Assuming no priors - get_robot_R_idxs
> In get_robot_R_idxs (line 4)
In write_result_to_tum (line 38)
In cora_python_interface (line 54)
[evaluate_utils.py:349] utils.logging_utils INFO - Found PyFG file: /home/alex/catkin_ws/src/cora-experiments/data/single_drone/factor_graph.pyfg
[pyfg_text.py:686] py_factor_graph.utils.logging_utils INFO - Loaded factor graph in PyFG text format from /home/alex/catkin_ws/src/cora-experiments/data/single_drone/factor_graph.pyfg
Traceback (most recent call last):
  File "/home/alex/catkin_ws/src/cora-experiments/experiments/single_drone_experiments.py", line 34, in <module>
    run_experiments(pyfg, experiments, exp_config)
  File "/home/alex/catkin_ws/src/cora-experiments/experiments/utils/run_experiments.py", line 166, in run_experiments
    _perform_evaluation(
  File "/home/alex/catkin_ws/src/cora-experiments/experiments/utils/run_experiments.py", line 63, in _perform_evaluation
    make_evo_traj_plots(
  File "/home/alex/catkin_ws/src/cora-experiments/experiments/utils/evaluate_utils.py", line 546, in make_evo_traj_plots
    fig = plt.figure(figsize=(20, 10))
  File "/home/alex/anaconda3/envs/cora/lib/python3.10/site-packages/matplotlib/pyplot.py", line 934, in figure
    manager = new_figure_manager(
  File "/home/alex/anaconda3/envs/cora/lib/python3.10/site-packages/matplotlib/pyplot.py", line 464, in new_figure_manager
    _warn_if_gui_out_of_main_thread()
  File "/home/alex/anaconda3/envs/cora/lib/python3.10/site-packages/matplotlib/pyplot.py", line 441, in _warn_if_gui_out_of_main_thread
    canvas_class = cast(type[FigureCanvasBase], _get_backend_mod().FigureCanvas)
  File "/home/alex/anaconda3/envs/cora/lib/python3.10/site-packages/matplotlib/pyplot.py", line 280, in _get_backend_mod
    switch_backend(rcParams._get("backend"))  # type: ignore[attr-defined]
  File "/home/alex/anaconda3/envs/cora/lib/python3.10/site-packages/matplotlib/pyplot.py", line 342, in switch_backend
    module = importlib.import_module(cbook._backend_module_name(newbackend))
  File "/home/alex/anaconda3/envs/cora/lib/python3.10/importlib/__init__.py", line 126, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 1050, in _gcd_import
  File "<frozen importlib._bootstrap>", line 1027, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1006, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 688, in _load_unlocked
  File "<frozen importlib._bootstrap_external>", line 883, in exec_module
  File "<frozen importlib._bootstrap>", line 241, in _call_with_frames_removed
  File "/home/alex/anaconda3/envs/cora/lib/python3.10/site-packages/matplotlib/backends/backend_qt5agg.py", line 7, in <module>
    from .backend_qtagg import (    # noqa: F401, E402 # pylint: disable=W0611
  File "/home/alex/anaconda3/envs/cora/lib/python3.10/site-packages/matplotlib/backends/backend_qtagg.py", line 9, in <module>
    from .qt_compat import QT_API, QtCore, QtGui
  File "/home/alex/anaconda3/envs/cora/lib/python3.10/site-packages/matplotlib/backends/qt_compat.py", line 133, in <module>
    raise ImportError(
ImportError: Failed to import any of the following Qt binding modules: PyQt5, PySide2

PyQt5 is installed here, and solutions to similar issues (see 1, 2) have not provided a fix. In testing tiers_experiments.py and hat_experiments.py, it appears that forcing matplotlib's backend to 'QtAgg' provides a fix. This fix is not reproduced in the single_drone_experiments.py.