topic How to check vertical coordinate system ? in Python Questions

How to check vertical coordinate system ?

AmeyaNatu1 — Wed, 19 Aug 2015 10:30:45 GMT

I am creating Python tool box where I am collecting 4 Input raster layer from the user. However I want to check their vertical coordinate system and check whether all the layers have same coordinate system or not.

Re: How to check vertical coordinate system ?

DanPatterson_Retired — Thu, 20 Aug 2015 01:00:55 GMT

What have you tried? You will get better results if you present you stage so far so that people can comment on your code or at least the help file reference topics that you have examined.

Re: How to check vertical coordinate system ?

AmeyaNatu1 — Tue, 01 Sep 2015 09:21:24 GMT

Dan Patterson

I have tried with 'hasZPrecision' property of spatial reference object but i am not sure whether it is correct. I want to know the vertical coordinate system is present in raster or not. If yes then is it same with others or not.

Re: How to check vertical coordinate system ?

FreddieGibson — Tue, 01 Sep 2015 16:21:52 GMT

Have you tried collecting the SpatialReference object of the feature class, exporting it to a string and parsing the string representation for the VERTCS? For example, I created some data that uses Web Mercator and MSL_Height vertical system and it's coordinate system string is shown below.

PROJCS['WGS_1984_Web_Mercator_Auxiliary_Sphere',GEOGCS['GCS_WGS_1984',DATUM['D_WGS_1984',SPHEROID['WGS_1984',6378137.0,298.257223563]],PRIMEM['Greenwich',0.0],UNIT['Degree',0.0174532925199433]],PROJECTION['Mercator_Auxiliary_Sphere'],PARAMETER['False_Easting',0.0],PARAMETER['False_Northing',0.0],PARAMETER['Central_Meridian',0.0],PARAMETER['Standard_Parallel_1',0.0],PARAMETER['Auxiliary_Sphere_Type',0.0],UNIT['Meter',1.0]],VERTCS['MSL_Height',VDATUM['Mean_Sea_Level'],PARAMETER['Vertical_Shift',0.0],PARAMETER['Direction',1.0],UNIT['Meter',1.0]];-20037700 -30241100 10000;-100000 10000;-100000 10000;0.001;0.001;0.001;IsHighPrecision

I would assume that most vertical coordinate systems would have these VERTCS and VDATUM tags. If I needed to parse this information I'd just build a regular expression to search for the needed tags or I'd just use python to slice the string to get the portion I need.

Re: How to check vertical coordinate system ?

DanPatterson_Retired — Thu, 03 Sep 2015 02:55:45 GMT

Other the identifying of the z parameter, you can search the arcpy tree to see if there is anything direct

What is geoprocessing?—Help | ArcGIS for Desktop

I suspect not, so parsing the coordinate system is your only other option