Re: [UrbanSim-Users] algorithm for evaluating development constraints

Liming,

This helps. One thing I still don't understand is: what is the
relationship between development types and development constraints for
DPLCMs?

 From your explanation below, and my reading of the documentation/
source code, I don't see where development types are used at all.

Thanks,

Brian

On May 20, 2008, at 3:19 PM, Liming Wang wrote:

> Brian,
> The order of the constraints in the table doesn't matter. For a
> given gridcell, it'll first match constraints in development
> _constraints table that are applicable to it according to attributes
> with matched names in both tables" (plan_type_id, is_in_wetland,
> etc), then the most restrictive rule, i.e. the highest minimum
> values and the lowest maximum values among applicable constraints,
> applies for each type of restrictions (units, commercial_sqft and
> industrial_sqft).
>
> The implementation of the constraints is in the urbansim/datasets/
> gridcell_dataset.py, which is called in the capacity variables
> (urbansim.gridcell.developable_maximum_commercial_sqft and
> developable_minimum_commercial_sqft, etc) of the development project
> location choice model.
>
> Hope this helps.
> Liming.
>
> On Fri, May 16, 2008 at 11:25 AM, Brian Miles <Brian.Miles_at_uvm.edu>
> wrote:
>
> Hello,
>
> We're working on some scenarios and we need to understand how
> development constraints are evaluated so that we can interpret the
> results we are seeing.
>
> The documentation in the manual for this is thin. One thing we are
> wondering is, does the order in which constraints are listed in the
> table have any bearing on what development is allowed in a given
> gridcell?
>
> Could you point out where in the location choice model code
> development constraints are evaluated?
>
> Thanks,
>
> Brian
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Received on Thu May 29 2008 - 05:59:13 PDT