[Bug]: No module named 'ipywidgets'

[swsyoon]

PyBaMM Version

24.1

Python Version

3.11.9

Describe the bug

I am running tutorial 1 in jupyter lab (Version 4.1.6) at Miniforge ( https://github.com/conda-forge/miniforge/releases/latest/download/Miniforge3-Windows-x86_64.exe ) and error occurs when I execute sim.plot() .

Steps to Reproduce

Simply run the tutorial

Relevant log output

---------------------------------------------------------------------------
ModuleNotFoundError                       Traceback (most recent call last)
Cell In[5], line 1
----> 1 sim.plot()

File ~\AppData\Local\miniforge-pypy3\envs\pybamm\Lib\site-packages\pybamm\simulation.py:1054, in Simulation.plot(self, output_variables, **kwargs)
   1051 if output_variables is None:
   1052     output_variables = self._output_variables
-> 1054 self.quick_plot = pybamm.dynamic_plot(
   1055     self._solution, output_variables=output_variables, **kwargs
   1056 )
   1058 return self.quick_plot

File ~\AppData\Local\miniforge-pypy3\envs\pybamm\Lib\site-packages\pybamm\plotting\dynamic_plot.py:21, in dynamic_plot(*args, **kwargs)
     19 kwargs_for_class = {k: v for k, v in kwargs.items() if k != "testing"}
     20 plot = pybamm.QuickPlot(*args, **kwargs_for_class)
---> 21 plot.dynamic_plot(kwargs.get("testing", False))
     22 return plot

File ~\AppData\Local\miniforge-pypy3\envs\pybamm\Lib\site-packages\pybamm\plotting\quick_plot.py:666, in QuickPlot.dynamic_plot(self, testing, step)
    653 """
    654 Generate a dynamic plot with a slider to control the time.
    655 
   (...)
    663 
    664 """
    665 if pybamm.is_notebook():  # pragma: no cover
--> 666     import ipywidgets as widgets
    668     step = step or self.max_t / 100
    669     widgets.interact(
    670         lambda t: self.plot(t, dynamic=False),
    671         t=widgets.FloatSlider(
   (...)
    674         continuous_update=False,
    675     )

ModuleNotFoundError: No module named 'ipywidgets'

[kratman]

So in the first cell the install of pybamm with the plot dependencies is commented out. Probably just need to make sure those are installed. If that does not work then I will look into this further

[swsyoon]

I had to comment out due to another error which does not seem to change the result. Here is a screenshot after removing the comment. The same error appears when execute sim.plot()

[kratman]

It looks like the install failed with an error due to the comment after the -q flag, can you remove the comment in the first line and see if it installs correctly?

[swsyoon]

Removing the comment after the -q flag solves the error at the line but still sim.plot() generates the same error

[kratman]

Ok I will take a look then. Thanks for checking

[agriyakhetarpal]

We can consider declaring ipywidgets as an optional dependency under [plot].

[kratman]

We can consider declaring ipywidgets as an optional dependency under [plot].

Yeah still good to know why there is a difference with this setup

[agriyakhetarpal]

Yeah still good to know why there is a difference with this setup

I found the problem – pybamm.QuickPlot.dynamic_plot requires it, but the import is hidden inside the is_notebook() function, and therefore PyBaMM does not fail on import. I think adding it to the [plot] dependencies and replacing the import with import_optional_dependency() should be alright (along with corresponding changes in the installation guide).

[kratman]

@agriyakhetarpal, @swsyoon So I checked on both pip and anaconda packages, ipywidgets is a dependency of Jupyter. This sounds like it might be an issue with the miniforge version of Jupyter lab rather than an issue with PyBaMM itself

[agriyakhetarpal]

Thanks for checking – Miniforge is just the same as conda/mamba but tailored for the conda-forge channel rather than defaults. So, yes, the notebook should work without changes from our end.