CRS Compatibility Guide for Geospatial Python¶

This is meant to be a guide to help you along the way of you use pyproj.crs.CRS with other Python Geospatial libraries.

Note

WKT2 is the best format for storing your CRS according to the PROJ FAQ.

osgeo/gdal¶

https://github.com/osgeo/gdal

Converting from osgeo.osr.SpatialReference to pyproj.crs.CRS¶

from osgeo.osr import SpatialReference
from pyproj.crs import CRS

osr_crs = SpatialReference()
osr_crs.ImportFromEPSG(4326)
proj_crs = CRS.from_wkt(osr_crs.ExportToWkt())

Converting from pyproj.crs.CRS to osgeo.osr.SpatialReference¶

Warning

WKT2 is only supported in GDAL 3+

import osgeo
from osgeo.osr import SpatialReference
from pyproj.crs import CRS
from pyproj.enums import WktVersion

proj_crs = CRS.from_epsg(4326)

osr_crs = SpatialReference()
if osgeo.version_info.major < 3:
    osr_crs.ImportFromWkt(proj_crs.to_wkt(WktVersion.WKT1_GDAL))
else:
    osr_crs.ImportFromWkt(proj_crs.to_wkt())

rasterio¶

https://github.com/mapbox/rasterio

Converting from rasterio.crs.CRS to pyproj.crs.CRS¶

If you have rasterio >= 1.0.14, then you can pass in the rasterio.crs.CRS directly:

from rasterio.crs import CRS as RioCRS
from pyproj.crs import CRS

rio_crs = RioCRS.from_epsg(4326)
proj_crs = CRS.from_user_input(rio_crs)

Otherwise, you should use the wkt property:

from rasterio.crs import CRS as RioCRS
from pyproj.crs import CRS

rio_crs = RioCRS.from_epsg(4326)
proj_crs = CRS.from_wkt(rio_crs.wkt)

Converting from pyproj.crs.CRS to rasterio.crs.CRS¶

Warning

WKT2 is only supported in GDAL 3+

If you have rasterio >= 1.0.26 and GDAL 3+, then you can pass in the pyproj.crs.CRS directly:

from rasterio.crs import CRS as RioCRS
from pyproj.crs import CRS

proj_crs = CRS.from_epsg(4326)
rio_crs = RioCRS.from_user_input(proj_crs)

If you want to be compatible across GDAL/rasterio versions, you can do:

from distutils.version import LooseVersion

import rasterio
from rasterio.crs import CRS as RioCRS
from pyproj.crs import CRS
from pyproj.enums import WktVersion

proj_crs = CRS.from_epsg(4326)
if LooseVersion(rasterio.__gdal_version__) < LooseVersion("3.0.0")
    rio_crs = RioCRS.from_wkt(proj_crs.to_wkt(WktVersion.WKT1_GDAL))
else:
    rio_crs = RioCRS.from_wkt(proj_crs.to_wkt())

fiona¶

https://github.com/Toblerity/Fiona

Converting from fiona CRS to pyproj.crs.CRS¶

Fiona currently stores the CRS as a PROJ string dictionary in the crs attribute. As such, it is best to use the crs_wkt attribute.

It is also useful to know that plans exist to add CRS class. Related GitHub issue here.

Example:

from pyproj.crs import CRS
import fiona

with fiona.open(...) as fds:
    proj_crs = CRS.from_wkt(fds.crs_wkt)

Converting from pyproj.crs.CRS for fiona¶

Warning

WKT2 is only supported in GDAL 3+

If you want to be compatible across GDAL versions, you can do:

from distutils.version import LooseVersion

import fiona

proj_crs = CRS.from_epsg(4326)

if LooseVersion(fiona.__gdal_version__) < LooseVersion("3.0.0"):
    fio_crs = proj_crs.to_wkt(WktVersion.WKT1_GDAL)
else:
    # GDAL 3+ can use WKT2
    fio_crs = dc_crs.to_wkt()

# with fiona.open(..., "w", crs_wkt=fio_crs) as fds:
#     ...

geopandas¶

https://github.com/geopandas/geopandas

Also see the geopandas guide for upgrading to use pyproj CRS class

Preparing pyproj.crs.CRS for geopandas¶

import fiona
import geopandas
from pyproj.crs import CRS
from pyproj.enums import WktVersion

proj_crs = CRS.from_epsg(4326)

if LooseVersion(geopandas.__version__) >= LooseVersion("0.7.0"):
    # geopandas uses pyproj.crs.CRS
    geo_crs = proj_crs
elif LooseVersion(geopandas.__version__) >= LooseVersion("0.6.0"):
    # this version of geopandas uses always_xy=True so WKT version is safe
    if LooseVersion(fiona.__gdal_version__) < LooseVersion("3.0.0"):
        geo_crs = proj_crs.to_wkt(WktVersion.WKT1_GDAL)
    else:
        # GDAL 3+ can use WKT2
        geo_crs = dc_crs.to_wkt()
else:
    geo_crs = dc_crs.to_proj4()

geopandas to pyproj.crs.CRS¶

pyproj.crs.CRS.from_user_input() can handle anything across the geopandas versions. The only gotcha would be if it is None.

import geopandas
from pyproj.crs import CRS

gdf = geopandas.read_file(...)
proj_crs = CRS.from_user_input(gdf.crs)

cartopy¶

https://github.com/SciTools/cartopy

This may change in the future: Port to use pyproj v2

Preparing pyproj.crs.CRS for cartopy.crs.CRS¶

import cartopy.crs as ccrs
from pyproj.crs import CRS

proj_crs = CRS.from_epsg(4326)
globe = ccrs.Globe(
    ellipse=None,
    semimajor_axis=proj_crs.ellipsoid.semi_major_metre,
    semiminor_axis=proj_crs.ellipsoid.semi_minor_metre,
    inverse_flattening=proj_crs.ellipsoid.inverse_flattening,
)
proj_dict = proj_crs.to_dict()
proj_dict["pm"] = proj_crs.prime_meridian.longitude
cart_crs = ccrs.CRS(proj_dict, globe=globe)

Preparing cartopy.crs.CRS for pyproj.crs.CRS¶

from cartopy.crs import PlateCarree
from pyproj.crs import CRS

cart_crs = PlateCarree()
proj_crs = CRS.from_dict(cart_crs.proj4_params)

pycrs¶

https://github.com/karimbahgat/PyCRS

Warning

Currently does not support WKT2

Preparing pyproj.crs.CRS for pycrs¶

import pycrs
from pyproj.crs import CRS

proj_crs = CRS.from_epsg(4326)
py_crs = pycrs.parse.from_ogc_wkt(proj_crs.to_wkt("WKT1_GDAL"))

Preparing cartopy.crs.CRS for pyproj.crs.CRS¶

import pycrs
from pyproj.crs import CRS

py_crs = pycrs.parse.from_epsg_code(4326)
proj_crs = CRS.from_wkt(py_crs.to_ogc_wkt())