Rename rHEALPix to RectangularHealpix.

SciTools · Feb 23, 2018 · 6886196 · 6886196
1 parent 89d6076
commit 6886196
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Showing 3 changed files with 29 additions and 24 deletions.
diff --git a/docs/source/crs/projections.rst b/docs/source/crs/projections.rst
@@ -414,34 +414,34 @@ OSNI
     ax.gridlines()
 
 
-SouthPolarStereo
-----------------
+RectangularHealpix
+------------------
 
-.. autoclass:: cartopy.crs.SouthPolarStereo
+.. autoclass:: cartopy.crs.RectangularHealpix
 
 .. plot::
 
     import matplotlib.pyplot as plt
     import cartopy.crs as ccrs
 
-    plt.figure(figsize=(3, 3))
-    ax = plt.axes(projection=ccrs.SouthPolarStereo())
+    plt.figure(figsize=(4, 3))
+    ax = plt.axes(projection=ccrs.RectangularHealpix())
     ax.coastlines(resolution='110m')
     ax.gridlines()
 
 
-rHEALPix
---------
+SouthPolarStereo
+----------------
 
-.. autoclass:: cartopy.crs.rHEALPix
+.. autoclass:: cartopy.crs.SouthPolarStereo
 
 .. plot::
 
     import matplotlib.pyplot as plt
     import cartopy.crs as ccrs
 
-    plt.figure(figsize=(4, 3))
-    ax = plt.axes(projection=ccrs.rHEALPix())
+    plt.figure(figsize=(3, 3))
+    ax = plt.axes(projection=ccrs.SouthPolarStereo())
     ax.coastlines(resolution='110m')
     ax.gridlines()
 

diff --git a/lib/cartopy/crs.py b/lib/cartopy/crs.py
@@ -510,7 +510,7 @@ def filter_last(t):
 
         # filter out any non-valid linear rings
         processed_ls = [linear_ring for linear_ring in processed_ls if
-                        len(linear_ring.coords) > 2]
+                        len(linear_ring.coords) > 3]
 
         linear_rings = [sgeom.LinearRing(line) for line in processed_ls]
 
@@ -1955,16 +1955,19 @@ def y_limits(self):
                                           semiminor_axis=6371007.181))
 
 
-class rHEALPix(Projection):
+class RectangularHealpix(Projection):
     """
-    The rHEALPix projection is an extension of the HEALPix to present squares
-    (rather than triangles) at the north and south poles.
+    Also known as rHEALPix in proj.4, this projection is an extension of the
+    Healpix projection to present rectangles, rather than triangles, at the north
+    and south poles.
 
     Parameters
     ----------
     central_longitude
     north_square: int
         The position for the north pole square. Must be one of 0, 1, 2 or 3.
+        0 would have the north pole square aligned with the left-most square,
+        and 3 would be aligned with the right-most.
     south_square: int
         The position for the south pole square. Must be one of 0, 1, 2 or 3.
 
@@ -1982,24 +1985,25 @@ def __init__(self, central_longitude=0, north_square=0, south_square=0):
                         ('north_square', north_square),
                         ('south_square', south_square),
                         ('lon_0', central_longitude)]
-        super(rHEALPix, self).__init__(proj4_params)
+        super(RectangularHealpix, self).__init__(proj4_params)
 
         # Boundary is based on units of m, with a standard spherical ellipse.
         # The hard-coded scale is the reason for not accepting the globe
         # keyword. The scale changes based on the size of the semi-major axis.
         nrth_x_pos = (north_square - 2) * 1e7
         sth_x_pos = (south_square - 2) * 1e7
-        top = 5.05e6
+        top = 5.03e6
+        max_v = 2e7
 
-        points = [[2e7, -5e6],
-                  [2e7, top],
+        points = [[max_v, -5e6],
+                  [max_v, top],
                   [nrth_x_pos + 1e7, top],
                   [nrth_x_pos + 1e7, 1.5e7],
                   [nrth_x_pos, 1.5e7],
                   [nrth_x_pos, top],
-                  [-2e7, top]]
+                  [-max_v, top]]
         if south_square != 0:
-            points.append([-2e7, -top])
+            points.append([-max_v, -top])
         points.extend([[sth_x_pos, -5e6],
                        [sth_x_pos, -1.5e7],
                        [sth_x_pos + 1e7, -1.5e7],

diff --git a/lib/cartopy/tests/test_crs.py b/lib/cartopy/tests/test_crs.py
@@ -225,17 +225,18 @@ def test_utm(self):
                              decimal=1)
 
 
-def test_rHEALPix_defaults():
-    crs = ccrs.rHEALPix()
+def test_RectangularHealpix_defaults():
+    crs = ccrs.RectangularHealpix()
     assert crs.proj4_params == {'ellps': 'WGS84',
                                 'lon_0': 0,
                                 'north_square': 0,
                                 'proj': 'rhealpix',
                                 'south_square': 0}
 
 
-def test_rHEALPix_params():
-    crs = ccrs.rHEALPix(central_longitude=20, north_square=1, south_square=2)
+def test_RectangularHealpix_params():
+    crs = ccrs.RectangularHealpix(central_longitude=20, north_square=1,
+                                  south_square=2)
     assert crs.proj4_params == {'ellps': 'WGS84',
                                 'lon_0': 20,
                                 'north_square': 1,