Add enums GridRegistration and GridType for grid registration and type (#3693)

Author: seisman

doc/_templates/autosummary/enums.rst

@@ -0,0 +1,7 @@
+{{ fullname | escape | underline }}
+
+.. currentmodule:: {{ module }}
+
+.. autoclass:: {{ objname }}
+    :members:
+    :member-order: bysource

doc/api/index.rst

@@ -195,6 +195,20 @@ Getting metadata from tabular or grid data:
     info
     grdinfo
 
+Enums
+-----
+
+.. currentmodule:: pygmt.enums
+
+.. autosummary::
+    :toctree: generated
+    :nosignatures:
+    :template: autosummary/enums.rst
+
+    GridRegistration
+    GridType
+
+.. currentmodule:: pygmt
 
 Miscellaneous
 -------------
@@ -205,8 +219,6 @@ Miscellaneous
     which
     show_versions
 
-.. currentmodule:: pygmt
-
 Datasets
 --------
 

pygmt/enums.py

@@ -37,3 +37,21 @@ class GridFormat(IntEnum):
     GD = 22  #: Import through GDAL
     EI = 23  #: ESRI Arc/Info ASCII Grid Interchange format (ASCII integer)
     EF = 24  #: ESRI Arc/Info ASCII Grid Interchange format (ASCII float)
+
+
+class GridRegistration(IntEnum):
+    """
+    Enum for the grid registration.
+    """
+
+    GRIDLINE = 0  #: Gridline registration
+    PIXEL = 1  #: Pixel registration
+
+
+class GridType(IntEnum):
+    """
+    Enum for the grid type.
+    """
+
+    CARTESIAN = 0  #: Cartesian grid
+    GEOGRAPHIC = 1  #: Geographic grid