Merge branch 'MR_issue67' into 'master'

improve grid size checks for GL

See merge request !56

nifty/spaces/gl_space/gl_space.py

@@ -205,10 +205,9 @@ class GLSpace(Space):
 
     def _parse_nlat(self, nlat):
         nlat = int(nlat)
-        if nlat < 2:
-            raise ValueError("nlat must be greater than 2.")
-        elif nlat % 2 != 0:
-            raise ValueError("nlat must be a multiple of 2.")
+        if nlat < 1:
+            raise ValueError(
+                "nlat must be a positive number.")
         return nlat
 
     def _parse_nlon(self, nlon):
@@ -216,9 +215,8 @@ class GLSpace(Space):
             nlon = 2 * self.nlat - 1
         else:
             nlon = int(nlon)
-            if nlon != 2 * self.nlat - 1:
-                self.logger.warn("nlon was set to an unrecommended value: "
-                                 "nlon <> 2*nlat-1.")
+            if nlon < 1:
+                raise ValueError("nlon must be a positive number.")
         return nlon
 
     # ---Serialization---

test/test_spaces/test_gl_space.py

@@ -37,10 +37,7 @@ CONSTRUCTOR_CONFIGS = [
             'total_volume': 4 * np.pi,
             'dtype': np.dtype('float64')
             }],
-        [1, None, None, {
-            'error': ValueError
-            }],
-        [5, None, None, {
+        [0, None, None, {
             'error': ValueError
             }]
     ]