Visualization Tutorial

[nicolas-starck]

When running the Visualization Tutorial for "Latest" with Mesa 3.1.0, the basic dashboard throws a ValueError for a missing model parameter - "Missing required model parameter: n".

Expected behavior
The expected behavior was the creation of the embedded page in the Jupyter Lab environment to interact with the MoneyModel.

To Reproduce
I am using the provided code for the MoneyModel, MoneyAgent, and compute_gini provided in the Introductory Tutorial in the "Additional agent reporter" section with the provided code from Part 1 of the Visualization Tutorial in a Jupyter Lab environment.

Additional context
I am running Jupyter Lab 4.2.5 on MacOS Sequoia 15.1.1

[quaquel]

I am unable to reproduce this problem on my machine using MESA 3.1, and the code provided in the docs folder of this repo.

My hunch (combined with the info on elements) is that the version of the MoneyModel you are using is not correct.

I have

class MoneyModel(mesa.Model):
    """A model with some number of agents."""

    def __init__(self, n=10, width=10, height=10, seed=None):
        """Initialize a MoneyModel instance.

        Args:
            N: The number of agents.
            width: width of the grid.
            height: Height of the grid.
        """
        super().__init__(seed=seed)
        self.num_agents = n
        self.grid = mesa.space.MultiGrid(width, height, True)

Where did you get the code for the money model from? Did you take it from the introductory tutorial?

[nicolas-starck]

Yes, I am getting the error from my reproduced MoneyModel code and the code copied from the end of the Introductory Tutorial. The code below is what I was using for the model. class MoneyModel(mesa.Model): """A model with some number of agents.""" def __init__(self, n, width, height, seed=None): super().__init__(seed=seed) self.num_agents = n self.grid = mesa.space.MultiGrid(width, height, True) self.running = True # Create agents for _ in range(self.num_agents): a = MoneyAgent(self) # Add the agent to a random grid cell x = self.random.randrange(self.grid.width) y = self.random.randrange(self.grid.height) self.grid.place_agent(a, (x, y)) self.datacollector = mesa.DataCollector( model_reporters={"Gini": compute_gini}, agent_reporters={"Wealth": "wealth", "Steps_not_given": "steps_not_given"}, ) def step(self): self.datacollector.collect(self) self.agents.shuffle_do("move") self.agents.shuffle_do("give_money")

[quaquel]

Ok, just change the signature to the one from my snippet and you should be good to go.

so use def __init__(self, n=10, width=10, height=10, seed=None): instead of def __init__(self, n, width, height, seed=None).

The underlying issue that needs to be fixed is to to update the introductory tutorial to use keywords only on all model classes.

[EwoutH]

Thanks for reporting this issue and finding the root cause of it.

I think a more structural solution, would be to let SolaraViz give a proper warning that notifies the user that not all arguments are keyword arguments.

[quaquel]

#2510 is adding this warning.

[tleung24]

I am currently encountering the same issue as originally mentioned. I implemented the recommended change to def__init__ which fixed the error but is not giving me the expected output. My output is just the blank white bar at the bottom.

Versions I'm running:
MESA 3.1.0
Windows 11
Visual Studio Code 1.88.1

[quaquel]

Does it say anything in the bar? This is most likely an issue in solara/javascript. I have seen others with similar issues but I so far haven't been able to figure out what is going on.

[nicolas-starck]

The offered solution worked to resolve the ValueError, however I am also seeing an empty cell output now that the code is executing. If this is likely something distinct, we can open a new issue for it.

[tpike3]

@nicolas-starck and @tleung24 That is a jupyter version issue; you need to update your version of jupyter

[nicolas-starck]

@tpike3 - I just updated to jupyterlab 4.3.2 and see the same behavior.

[tpike3]

@tpike3 - I just updated to jupyterlab 4.3.2 and see the same behavior.

HMMM @nicolas-starck can you share your

iypthon
ipyvue
ipvuetify
and solara version

I am 90% sure this is a dependency issue, I am just hoping it is not a Mac issue.

[quaquel]

I am on a mac and for me, everything works fine. So, it can work on a. mac.