Merge 952edad into b0a1f07

pyproj/_crs.pyx

@@ -3,19 +3,23 @@ from collections import OrderedDict
 
 from pyproj.compat import cstrencode, pystrdecode
 from pyproj._datadir cimport get_pyproj_context
+from pyproj.enum import WktVersion, ProjVersion
 from pyproj.exceptions import CRSError
 
+
 cdef cstrdecode(const char *instring):
     if instring != NULL:
         return pystrdecode(instring)
     return None
 
+
 cdef decode_or_undefined(const char* instring):
     pystr = cstrdecode(instring)
     if pystr is None:
         return "undefined"
     return pystr
 
+
 def is_wkt(proj_string):
     """
     Check if the input projection string is in the Well-Known Text format.
@@ -33,7 +37,7 @@ def is_wkt(proj_string):
     return proj_context_guess_wkt_dialect(NULL, tmp_string) != PJ_GUESSED_NOT_WKT
 
 
-cdef _to_wkt(PJ_CONTEXT* projctx, PJ* projobj, version="WKT2_2018", pretty=False):
+cdef _to_wkt(PJ_CONTEXT* projctx, PJ* projobj, version=WktVersion.WKT2_2018, pretty=False):
     """
     Convert a PJ object to a wkt string.
 
@@ -50,16 +54,16 @@ cdef _to_wkt(PJ_CONTEXT* projctx, PJ* projobj, version="WKT2_2018", pretty=False
     """
     # get the output WKT format
     supported_wkt_types = {
-        "WKT2_2015": PJ_WKT2_2015,
-        "WKT2_2015_SIMPLIFIED": PJ_WKT2_2015_SIMPLIFIED,
-        "WKT2_2018": PJ_WKT2_2018,
-        "WKT2_2018_SIMPLIFIED": PJ_WKT2_2018_SIMPLIFIED,
-        "WKT1_GDAL": PJ_WKT1_GDAL,
-        "WKT1_ESRI": PJ_WKT1_ESRI
+        WktVersion.WKT2_2015: PJ_WKT2_2015,
+        WktVersion.WKT2_2015_SIMPLIFIED: PJ_WKT2_2015_SIMPLIFIED,
+        WktVersion.WKT2_2018: PJ_WKT2_2018,
+        WktVersion.WKT2_2018_SIMPLIFIED: PJ_WKT2_2018_SIMPLIFIED,
+        WktVersion.WKT1_GDAL: PJ_WKT1_GDAL,
+        WktVersion.WKT1_ESRI: PJ_WKT1_ESRI
     }
     cdef PJ_WKT_TYPE wkt_out_type
     try:
-        wkt_out_type = supported_wkt_types[version.upper()]
+        wkt_out_type = supported_wkt_types[WktVersion(version)]
     except KeyError:
         raise ValueError(
             "Invalid version supplied '{}'. "
@@ -82,27 +86,28 @@ cdef _to_wkt(PJ_CONTEXT* projctx, PJ* projobj, version="WKT2_2018", pretty=False
     return cstrdecode(proj_string)
 
 
-cdef _to_proj4(PJ_CONTEXT* projctx, PJ* projobj, version=4):
+cdef _to_proj4(PJ_CONTEXT* projctx, PJ* projobj, version=ProjVersion.PROJ_4):
     """
     Convert the projection to a PROJ.4 string.
 
     Parameters
     ----------
-    version: int
-        The version of the PROJ.4 output. Default is 4.
+    version: ~pyproj.enum.ProjVersion
+        The version of the PROJ.4 output. 
+        Default is :attr:`~pyproj.enum.ProjVersion.PROJ_4`.
 
     Returns
     -------
     str: The PROJ.4 string.
     """
     # get the output PROJ.4 format
     supported_prj_types = {
-        4: PJ_PROJ_4,
-        5: PJ_PROJ_5,
+        ProjVersion.PROJ_4: PJ_PROJ_4,
+        ProjVersion.PROJ_5: PJ_PROJ_5,
     }
     cdef PJ_PROJ_STRING_TYPE proj_out_type
     try:
-        proj_out_type = supported_prj_types[version]
+        proj_out_type = supported_prj_types[ProjVersion(version)]
     except KeyError:
         raise ValueError(
             "Invalid version supplied '{}'. "
@@ -307,8 +312,9 @@ cdef class Base:
 
         Parameters
         ----------
-        version: str
-            The version of the WKT output. Default is WKT2_2018.
+        version: ~pyproj.enum.WktVersion
+            The version of the WKT output.
+            Default is :attr:`~pyproj.enum.WktVersion.WKT2_2018`.
         pretty: bool
             If True, it will set the output to be a multiline string. Defaults to False.
  
@@ -1037,14 +1043,15 @@ cdef class CoordinateOperation(Base):
             )
         return self._grids
 
-    def to_proj4(self, version=5):
+    def to_proj4(self, version=ProjVersion.PROJ_5):
         """
         Convert the projection to a PROJ.4 string.
 
         Parameters
         ----------
-        version: int
-            The version of the PROJ.4 string. Default is 5.
+        version: ~pyproj.enum.ProjVersion
+            The version of the PROJ.4 output. 
+            Default is :attr:`~pyproj.enum.ProjVersion.PROJ_5`.
 
         Returns
         -------
@@ -1270,14 +1277,15 @@ cdef class _CRS(Base):
 
         return self._sub_crs_list
 
-    def to_proj4(self, version=4):
+    def to_proj4(self, version=ProjVersion.PROJ_4):
         """
         Convert the projection to a PROJ.4 string.
 
         Parameters
         ----------
-        version: int
-            The version of the PROJ.4 output. Default is 4.
+        version: ~pyproj.enum.ProjVersion
+            The version of the PROJ.4 output. 
+            Default is :attr:`~pyproj.enum.ProjVersion.PROJ_4`.
 
         Returns
         -------

pyproj/_transformer.pyx

@@ -1,26 +1,12 @@
 include "base.pxi"
 
 from pyproj._crs cimport _CRS
-from pyproj.compat import cstrencode, pystrdecode
 from pyproj._datadir cimport get_pyproj_context
+from pyproj.compat import cstrencode, pystrdecode
+from pyproj.enum import TransformDirection
 from pyproj.exceptions import ProjError
 
 
-_PJ_DIRECTION_MAP = {
-    "forward": PJ_FWD,
-    "inverse": PJ_INV,
-    "ident": PJ_IDENT,
-}
-
-cdef PJ_DIRECTION get_direction(direction):
-    try:
-        return _PJ_DIRECTION_MAP[direction]
-    except KeyError:
-        raise ValueError(
-            "Invalid direction supplied '{}'. "
-            "Only {} are supported."
-            .format(direction, tuple(_PJ_DIRECTION_MAP)))
-
 cdef class _Transformer:
     def __cinit__(self):
         self.projpj = NULL
@@ -92,7 +78,7 @@ cdef class _Transformer:
     def _transform(self, inx, iny, inz, intime, direction, radians, errcheck):
         if self.projections_exact_same or (self.projections_equivalent and self.skip_equivalent):
             return
-        cdef PJ_DIRECTION pj_direction = get_direction(direction)
+        cdef PJ_DIRECTION pj_direction = <PJ_DIRECTION>direction
         # private function to call pj_transform
         cdef void *xdata
         cdef void *ydata
@@ -183,7 +169,7 @@ cdef class _Transformer:
     ):
         if self.projections_exact_same or (self.projections_equivalent and self.skip_equivalent):
             return
-        cdef PJ_DIRECTION pj_direction = get_direction(direction)
+        cdef PJ_DIRECTION pj_direction = <PJ_DIRECTION>direction
         # private function to itransform function
         cdef:
             void *buffer

pyproj/enum.py

@@ -0,0 +1,48 @@
+"""
+This module contains enumerations used in pyproj.
+
+"""
+from enum import Enum, IntEnum
+
+
+class WktVersion(Enum):
+    """
+    Supported CRS WKT string versions
+    """
+
+    #: WKT Version 2 from 2015
+    WKT2_2015 = "WKT2_2015"
+    #: WKT Version 2 from 2015 Simplified
+    WKT2_2015_SIMPLIFIED = "WKT2_2015_SIMPLIFIED"
+    #: WKT Version 2 from 2018
+    WKT2_2018 = "WKT2_2018"
+    #: WKT Version 2 from 2018 Simplified
+    WKT2_2018_SIMPLIFIED = "WKT2_2018_SIMPLIFIED"
+    #: WKT Version 1 GDAL Style
+    WKT1_GDAL = "WKT1_GDAL"
+    #: WKT Version 1 ESRI Style
+    WKT1_ESRI = "WKT1_ESRI"
+
+
+class ProjVersion(IntEnum):
+    """
+    Supported CRS PROJ string versions
+    """
+
+    #: PROJ String version 4
+    PROJ_4 = 4
+    #: PROJ String version 5
+    PROJ_5 = 5
+
+
+class TransformDirection(IntEnum):
+    """
+    Supported transform directions
+    """
+
+    #: Forward direction
+    FORWARD = 1
+    #: Inverse direction
+    INVERSE = -1
+    #: Do nothing
+    IDENT = 0

pyproj/transformer.py

@@ -23,6 +23,7 @@
 from pyproj import CRS, Proj
 from pyproj._transformer import _Transformer
 from pyproj.compat import cstrencode
+from pyproj.enum import TransformDirection
 from pyproj.utils import _convertback, _copytobuffer
 
 try:
@@ -125,7 +126,7 @@ def transform(
         tt=None,
         radians=False,
         errcheck=False,
-        direction="forward",
+        direction=TransformDirection.FORWARD,
     ):
         """
         Transform points between two coordinate systems.
@@ -148,9 +149,9 @@ def transform(
             If True an exception is raised if the transformation is invalid.
             By default errcheck=False and an invalid transformation 
             returns ``inf`` and no exception is raised.
-        direction: str, optional
-            The direction of the transform ("forward", "inverse", "ident").
-            Default is "forward".
+        direction: ~pyproj.enum.TransformDirection, optional
+            The direction of the transform.
+            Default is :attr:`~pyproj.enum.TransformDirection.FORWARD`.
 
 
         Example:
@@ -217,7 +218,7 @@ def itransform(
         time_3rd=False,
         radians=False,
         errcheck=False,
-        direction="forward",
+        direction=TransformDirection.FORWARD,
     ):
         """
         Iterator/generator version of the function pyproj.Transformer.transform.

setup.py

@@ -235,4 +235,5 @@ def get_version():
     packages=["pyproj"],
     ext_modules=get_extension_modules(),
     package_data=get_package_data(),
+    install_requires=["enum34"] if sys.version_info < (3, 4) else None,
 )

sphinx/api/enum.rst

@@ -0,0 +1,13 @@
+Enumerations
+============
+
+.. autoclass:: pyproj.enum.WktVersion
+    :members:
+
+
+.. autoclass:: pyproj.enum.ProjVersion
+    :members:
+
+
+.. autoclass:: pyproj.enum.TransformDirection
+    :members:

sphinx/api/index.rst

@@ -10,5 +10,6 @@ API Documentation
    geod
    transformer
    list
+   enum
    datadir
-   exceptions
+   exceptions

test/test_crs.py

@@ -2,6 +2,7 @@
 
 from pyproj import CRS
 from pyproj.crs import CoordinateOperation, Datum, Ellipsoid, PrimeMeridian
+from pyproj.enum import ProjVersion, WktVersion
 from pyproj.exceptions import CRSError
 
 
@@ -550,3 +551,20 @@ def test_coordinate_operation_towgs84_seven():
 def test_coordinate_operation_towgs84_missing():
     crs = CRS(init="epsg:3004")
     assert crs.coordinate_operation.towgs84 == []
+
+
+def test_to_wkt_enum():
+    crs = CRS.from_epsg(4326)
+    assert crs.to_wkt("WKT1_GDAL") == crs.to_wkt(WktVersion.WKT1_GDAL)
+    assert crs.to_wkt("WKT2_2018") == crs.to_wkt(WktVersion.WKT2_2018)
+    assert crs.to_wkt("WKT2_2018_SIMPLIFIED") == \
+        crs.to_wkt(WktVersion.WKT2_2018_SIMPLIFIED)
+    assert crs.to_wkt("WKT2_2015") == crs.to_wkt(WktVersion.WKT2_2015)
+    assert crs.to_wkt("WKT2_2015_SIMPLIFIED") == \
+        crs.to_wkt(WktVersion.WKT2_2015_SIMPLIFIED)
+
+
+def test_to_proj4_enum():
+    crs = CRS.from_epsg(4326)
+    assert crs.to_proj4(4) == crs.to_proj4(ProjVersion.PROJ_4)
+    assert crs.to_proj4(5) == crs.to_proj4(ProjVersion.PROJ_5)

test/test_transformer.py

@@ -4,6 +4,7 @@
 
 import pyproj
 from pyproj import Proj, Transformer, itransform, transform
+from pyproj.enum import TransformDirection
 from pyproj.exceptions import ProjError
 
 
@@ -306,7 +307,7 @@ def test_4d_transform__inverse():
             yy=778956.4532640711,
             zz=5248216.453456361,
             tt=2008.75,
-            direction="inverse",
+            direction=TransformDirection.INVERSE,
         ),
         (3513638.19380, 778956.45250, 5248216.46900, 2008.75),
     )
@@ -316,7 +317,8 @@ def test_transform_direction():
     forward_transformer = Transformer.from_crs(4326, 3857)
     inverse_transformer = Transformer.from_crs(3857, 4326)
     assert inverse_transformer.transform(
-        -33, 24, direction="inverse"
+        -33, 24, direction=TransformDirection.INVERSE
     ) == forward_transformer.transform(-33, 24)
     ident_transformer = Transformer.from_crs(4326, 3857)
-    ident_transformer.transform(-33, 24, direction="ident") == (-33, 24)
+    ident_transformer.transform(-33, 24, direction=TransformDirection.IDENT) ==\
+        (-33, 24)