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I am having trouble getting GDAL to read a file geodatabase with data projected in NAD83(2011) State Plane Arizona Central FIPS 0202. I have developed the following code:

# standard imports
import sys

# import OGR
from osgeo import ogr

# use OGR specific exceptions
ogr.UseExceptions()

# get the driver
driver = ogr.GetDriverByName("OpenFileGDB")
print ("I made it to line 12")
# opening the FileGDB
try:
    gdb = driver.Open("CM_2009_DEM.gdb", 0)

except Exception, e:
    print e
    sys.exit()

The data can be downloaded here. I am new to python and GDAL and I am simply trying to list out the items in the specified geodatabase. When i run the code I get the following error:

EPSG PCS/GCS code 102988 not found in EPSG support files.  IS this a valid EPSG coordinate system?

The projection was made in house and there hasn't been an EPSG of ESRI code assigned to it yet. I know its valid, but is there a way to make GDAL think its valid?

The projection file reads as follows:

PROJCS["NAD_1983_2011_StatePlane_Arizona_Central_FIPS_0202",GEOGCS["GCS_NAD_1983_2011",DATUM["D_NAD_1983_2011",SPHEROID["GRS_1980",6378137.0,298.257222101]],PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]],PROJECTION["Transverse_Mercator"],PARAMETER["False_Easting",213360.0],PARAMETER["False_Northing",0.0],PARAMETER["Central_Meridian",-111.9166666666667],PARAMETER["Scale_Factor",0.9999],PARAMETER["Latitude_Of_Origin",31.0],UNIT["Meter",1.0]]
dubbbdan
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  • EPSG does have this definition (since October 2013): 6404. – mkennedy May 12 '15 at 19:44
  • I wodner what the 102988 number from the error means. – dubbbdan May 13 '15 at 20:33
  • The geodatabase probably lists 102988 as the feature classes well-known ID / coordinate system ID. Aka, it was written before Esri changed our 102988 entry to use EPSG 6404 instead. The GDAL support files might not have either WKID or possibly only the latter one. – mkennedy May 13 '15 at 20:38
  • Thats correct. Is there a way to change it to 6404? – dubbbdan May 13 '15 at 22:12

1 Answers1

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The code number 102988 is not an EPSG one, but defined by ESRI.

If you run gdalsrsinfo on the projection file, it reports:

+proj=tmerc +lat_0=31 +lon_0=-111.9166666666667 +k=0.9999 +x_0=213360 +y_0=0 +ellps=GRS80 +units=m +no_defs

You have to create a custom CRS with these parameters to work with the dataset.

GDAL comes with a similar CRS named EPSG:102249 NAD_1983_HARN_StatePlane_Arizona_Central_FIPS_0202 (also defined by ESRI, not EPSG) using the same parameters.

There might be a small datum shift between the two, but ESRI does not put any datum shift inside their projection files.

You can use real EPSG codes 26949, 2762 or 3478 as well, which all share the same parameters inside GDAL.

AndreJ
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  • Thanks for the reply, but you have not addressed my question. Are you are suggesting the 2002(HARN) and 2011 realizations of NAD83 are the same? The UNIT["Degree",] field is different between the projection I need to use and the ones defined by ESRI and ESPG. I need to find a way to tell GDAL the projection associated with the geodatabase is valid. Is that possible? – dubbbdan May 11 '15 at 20:00
  • The difference between 2002 and 2011 would be in the datum shift, but that is not part of the projection file information. For the UNIT: both are in meters (don't get confused with the GCS unit of degrees). – AndreJ May 12 '15 at 03:57
  • For the datum shift, see http://gis.stackexchange.com/questions/91414/geographic-transformations-in-alaska-between-nad83-and-wgs84 and the links given there. – AndreJ May 12 '15 at 05:18