Generating surrogates for EGrid using the new PostgreSQL Surrogate Tool

I am able to use the new PostgreSQL Surrogate Tool to generate surrogates for a RegularGrid. However, I couldn’t figure out how to use it to generate surrogates for EGrid. Is EGrid supported by the PostgreSQL Surrogate Tool?

Can you be more specific about EGrid? What is EGrid? We are not familiar with it.

Thank you very much BH for the response. EGrid is one of the three grid types supported by the Surrogate Tool. The other two are RegularGrid and Polygon, see

For Egrid, each grid cell is defined by the lat,lon of the center and four corners of the grid cell. Below is the definition of the first grid cell copied from the egrid definition example file (egrid_arc.dat) included in the SA package:

Thanks again!

could you send me some guide for new PostgreSQL tool? I am working on the surrogate file using the old srgtools. However, it works slowly.

I don’t think it has been officially released yet. However, scripts and instruction of how to use it are included in the latest SA-TOOLS version 4.3.2 downloadable from the CMAS website, see also for how to install this tool. I need it to generate surrogates for processing emissions using the EPA 2014/2014/2016 emissions inventory.

Junhua, We are getting close to releasing this product. We would appreciate your feedback on how it is working for you once it is released. I don’t have the exact release date but it should be sometime in the next few weeks.



@junhua.zhang. Egrid is not currently tested with upcoming PosgreSQL surrogate tool yet but conceptually it can be processed through PostgreSQL tool once you set Egrid as polygon output modeling domain shape.