setValue does not work for Variable Primitive

[herzogrh]

Currently, it does not seem possible to set Values for Agent Variables programmatically as detailed here. It seems to work well for eg. Stocks inside the Agent, but for Variables the following error occurs ([Height] being a variable primitive):

After looking into the code, it seems that there is no specific setValue function specified for variable primitives. Because of that, the default error is thrown.

[scottfr]

Hi Rico,

setValue() only works with primitives that are stateful, which are the Stock and State primitives. You could trying using a Stock instead of a Variable for your Height.

[herzogrh]

Hi Scott, thanks for the quick reply! Both work, but in case I want to let's say store a piece of text in an agent's attribute, calling setValue on a Stock primitive with a String (which works just fine) seems a little counterintuitive.

[herzogrh]

After experimenting more with ABMs and the simulation engine, I think that it would be useful to have a stateful primitive which stores attributes for each agent without being a state or a stock. For instance, if I want to store and update a target for each agent where it should move towards (instead of calculating this every timestep in an action). Then I encounter the following issue:

• I cannot update the target vector in an agent variable due to the issue described above
• I cannot call SetValue({x: 34, x: 34}) for a Stock variable, because I get the error SetValue([Primitive], Value) does not accept vectors for the parameter 'Value'.
• I cannot set a State Variable, because it only accepts true/false values

[scottfr]

Hi Rico,

I think it makes sense to allow setting vectors on stocks using SetValue. I'll try to support that in the next version.

You can also look into using a global variable to store a map of agent index -> value for all your agents. That should work too.

[herzogrh]

Hi Scott, thanks for the workaround with the global variable! Will look into that!