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Pollination Module: Empty Sequence? Where?

I keep getting: "encountered: max() arg is an empty sequence" when I run this module. What's missing?

Also, for the Guild excel sheet, what is the "Species Weight" column? I cannot find any documentation in the online documentation. I just entered 1 for all species. 

Thank you,


  • Also, is there a maximum of species I can use in the guild table? I collected 86 species of bees and want to put them in the model.
  • RichRich Administrator, NatCap Staff
    Hi, I'm not an expert in this model, but offhand it looks like it might not be parsing out the nesting and floral fields in the landcover attribute table.  From the sample data, this looks like these are supposed to have names like "N_cavity" (I think that's nesting) or "F_spring" (for floral?). 

    Does that make sense in the context of your problem?  Does your landcover attribute table have these header fields?

    For your second question, there's no hard limit to the max # of species in the guild table.
  • Thanks. I am still trying. I usually start with the practice dataset for all the modules to try and limt my own errors. I will make a fresh excel file and see if there aren't some hidden characters or something?

    What does the Species Weight column do? It is not mentioned in the online documentation.

    Thanks, NatCap.
  • RichRich Administrator, NatCap Staff
    Hi, I wasn't sure what species weight did either.  I agree it's not in the user's guide, but in the code it looks like it calculates species abudance by multiplying the nesting weight with the floral weight as well as an arbitrary species weight.  Offhand, it looks like a feature someone might have been adding once that was incomplete.  Looks safe to keep at 1.0.
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