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This is empty using Python .ImportFromEPSG(4326):

import osr
#this fails:
testSR = osr.SpatialReference()
testSR.ImportFromEPSG(4326)
print testSR.ExportToPrettyWkt()

#why did the import from EPSG fail above?
testSR.SetWellKnownGeogCS("WGS84")
print testSR.ExportToPrettyWkt()
GEOGCS["WGS 84",
DATUM["WGS_1984", and so on...
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Do you need to get the list using Python? Or would just getting the list work? – R.K. Dec 15 '12 at 7:06
What version of ogr are you using? – R.K. Dec 15 '12 at 14:00
help(osr) Help on module osr: NAME osr - # import osgeo.osr as a convenience FILE c:\python27\arcgis10.1\lib\site-packages\osr.py – Dave Dec 15 '12 at 14:28
testSR.ImportFromEPSG('4326')? Do you need to pass a str instead of an int? - Also, make sure to go back and accept some answers to your other questions. – Jay Laura Jan 14 at 14:40
1  
Make sure GDAL_DATA is set to the proper location. It may be that the EPSG import is failing because it can't find the files. – kyle Jan 14 at 20:28

2 Answers

up vote 0 down vote

You'll have to define test1 first

import osr
test1 = osr.SpatialReference() #define test1
test1.ImportFromEPSG(4326)
print test1.ExportToPrettyWkt()

Only then can you call the ExportToPrettyWkt() function. Which should result in the following output:

GEOGCS["WGS 84",
    DATUM["WGS_1984",
        SPHEROID["WGS 84",6378137,298.257223563,
            AUTHORITY["EPSG","7030"]],
        AUTHORITY["EPSG","6326"]],
    PRIMEM["Greenwich",0,
        AUTHORITY["EPSG","8901"]],
    UNIT["degree",0.0174532925199433,
        AUTHORITY["EPSG","9122"]],
    AUTHORITY["EPSG","4326"]]
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This returns an empty spatial reference: import osr testSR = osr.SpatialReference() testSR.ImportFromEPSG(4326) print testSR.ExportToPrettyWkt() – Dave Dec 15 '12 at 13:56
You mean the print statement does not print anything for you? – R.K. Dec 15 '12 at 13:57
Correct. testSR.ImportFromEPSG(4326); txtTest = testSR.ExportToPrettyWkt(); len(txtTest) is zero while testSR.SetWellKnownGeogCS("WGS84"); txtTest = testSR.ExportToPrettyWkt() returns a string of 357 chars – Dave Dec 15 '12 at 14:04
What is your question btw? Now I'm confused. Is it to fix the error or to get the list of ESPG values? Where can I get a list of EPSG values for common spatial references? Also, how did you install your osr and what version are you using? – R.K. Dec 15 '12 at 14:07
testSR.ImportFromEPSG(4326) returns an empty spatial reference osr is from: c:\python27\arcgis10.1\lib\site-packages\osr.py – Dave Dec 15 '12 at 14:10
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up vote 0 down vote

First, the real error was skipped, since ImportFromEPSG returned a non-zero error code:

from osgeo import osr
testSR = osr.SpatialReference()
res = testSR.ImportFromEPSG(4326)
if res != 0:
    raise RuntimeError(repr(res) + ': could not import from EPSG')
print testSR.ExportToPrettyWkt()

Now the cause. GDAL needs an environment variable GDAL_DATA to find and use projection info. If it is not available, then some things stop working. The SRID look-up codes are in GDAL_DATA, for instance. Check if you have it:

import os
'GDAL_PATH' in os.environ

if False, it should be added to either your system's environment variables, or you can add it in run-time:

if 'GDAL_DATA' not in os.environ:
    os.environ['GDAL_DATA'] = r'/path/to/gdal_data'
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