added reader for era data and adjusted the transformation of lons acc…

…ordingly

wavy/model_module.py

@@ -532,7 +532,10 @@ def _enforce_longitude_format(self):
         attrs['valid_max'] = 180
         attrs['valid_min'] = -180
         attrs['comments'] = 'forced to range: -180 to 180'
-        new.vars.lons.values = ((new.vars.lons.values + 180) % 360) - 180
+        try:
+            new.vars.lons.values = ((new.vars.lons.values + 180) % 360) - 180
+        except Exception as e:
+            new.vars.assign_coords({"lons": ((new.vars.lons.values + 180) % 360) - 180})
         return new
 
     def _enforce_meteorologic_convention(self):

wavy/model_readers.py

@@ -251,3 +251,37 @@ def read_ww3_unstructured_to_grid(**kwargs):
     from wavy.grid_readers import read_ww3_unstructured_to_grid
     ds = read_ww3_unstructured_to_grid(**kwargs)
     return ds
+
+
+def read_era(**kwargs):
+    pathlst = kwargs.get('pathlst')
+    nID = kwargs.get('nID')
+    fc_dates = kwargs.get('fc_dates')
+    varname = kwargs.get('varname')
+    ds_lst = []
+    # retrieve sliced data
+    for i in range(len(fc_dates)):
+        d = parse_date(fc_dates[i])
+        p = pathlst[i]
+        ds = xr.open_dataset(p)
+        ds_sliced = ds.sel({model_dict[nID]['vardef']['time']: d})
+        ds_sliced = ds_sliced[[varname,
+                               model_dict[nID]['vardef']['lons'],
+                               model_dict[nID]['vardef']['lats']]]
+
+        ds_lst.append(ds_sliced)
+
+    print(" Concatenate ...")
+    combined = xr.concat(ds_lst, model_dict[nID]['vardef']['time'],
+                         coords='minimal',
+                         data_vars='minimal',
+                         compat='override',
+                         combine_attrs='override',
+                         join='override')
+    print(" ... done concatenating")
+
+    print(' Build dataset')
+    print(' dataset ready!')
+
+    return combined
+