fix Coordinate -> IndexVariable

Author: Benoit Bovy

xarray/core/coordinates.py

@@ -245,8 +245,8 @@ def _names(self):
     @property
     def variables(self):
         level_coords = OrderedDict(
-            (k, self._data[v].variable.get_level_coord(k))
-            for k, v in self._data._level_coords.items())
+            (k, self._data[v].variable.get_level_variable(k))
+             for k, v in self._data._level_coords.items())
         return Frozen(level_coords)
 
 

xarray/core/dataarray.py

@@ -429,7 +429,7 @@ def _level_coords(self):
         level_coords = OrderedDict()
         for cname, var in self._coords.items():
             if var.ndim == 1:
-                level_names = var.to_coord().level_names
+                level_names = var.to_index_variable().level_names
                 if level_names is not None:
                     dim = var.dims[0]
                     level_coords.update({lname: dim for lname in level_names})

xarray/core/dataset.py

@@ -50,7 +50,7 @@ def _get_virtual_variable(variables, key, level_vars={}):
 
     if ref_name in level_vars:
         dim_var = variables[level_vars[ref_name]]
-        ref_var = dim_var.to_coord().get_level_coord(ref_name)
+        ref_var = dim_var.to_index_variable().get_level_variable(ref_name)
     else:
         ref_var = variables[ref_name]
 
@@ -447,7 +447,7 @@ def _level_coords(self):
         for cname in self._coord_names:
             var = self.variables[cname]
             if var.ndim == 1:
-                level_names = var.to_coord().level_names
+                level_names = var.to_index_variable().level_names
                 if level_names is not None:
                     dim = var.dims[0]
                     level_coords.update({lname: dim for lname in level_names})

xarray/core/formatting.py

@@ -212,7 +212,8 @@ def _summarize_coord_multiindex(coord, col_width, marker):
 def _summarize_coord_levels(coord, col_width, marker=u'-'):
     relevant_coord = coord[:30]
     return u'\n'.join(
-        [_summarize_var_or_coord(lname, relevant_coord.get_level_coord(lname),
+        [_summarize_var_or_coord(lname,
+                                 relevant_coord.get_level_variable(lname),
                                  col_width, marker=marker)
          for lname in coord.level_names])
 
@@ -237,7 +238,7 @@ def summarize_coord(name, var, col_width):
     show_values = is_index or _not_remote(var)
     marker = u'*' if is_index else u' '
     if is_index:
-        coord = var.variable.to_coord()
+        coord = var.variable.to_index_variable()
         if coord.level_names is not None:
             return u'\n'.join(
                 [_summarize_coord_multiindex(coord, col_width, marker),

xarray/core/indexing.py

@@ -216,8 +216,8 @@ def convert_label_indexer(index, label, index_name='', method=None,
 
 
 def get_dim_indexers(data_obj, indexers):
-    """Given an xarray data object and label based indexers, return a mapping
-    of indexers with only dimension names as keys.
+    """Given a xarray data object and label based indexers, return a mapping
+    of label indexers with only dimension names as keys.
 
     It groups multiple level indexers given on a multi-index dimension
     into a single, dictionary indexer for that dimension (Raise a ValueError

xarray/core/variable.py

@@ -1079,7 +1079,8 @@ class IndexVariable(Variable):
     def __init__(self, dims, data, attrs=None, encoding=None,
                  name=None, fastpath=False):
 
-        super(IndexVariable, self).__init__(dim, data, attrs, encoding, fastpath)
+        super(IndexVariable, self).__init__(dims, data, attrs, encoding,
+                                            fastpath)
         if self.ndim != 1:
             raise ValueError('%s objects must be 1-dimensional' %
                              type(self).__name__)
@@ -1183,7 +1184,7 @@ def to_index(self):
 
     @property
     def level_names(self):
-        """Return MultiIndex level names or None if Coordinate has no
+        """Return MultiIndex level names or None if this IndexVariable has no
         MultiIndex.
         """
         index = self.to_index()
@@ -1194,12 +1195,13 @@ def level_names(self):
 
     @level_names.setter
     def level_names(self, value):
-        raise AttributeError('cannot modify level names of Coordinate in-place')
+        raise AttributeError('cannot modify level names of '
+                             'IndexVariable in-place')
 
-    def get_level_coord(self, level):
-        """Return a new Coordinate from a given MultiIndex level."""
+    def get_level_variable(self, level):
+        """Return a new IndexVariable from a given MultiIndex level."""
         if self.level_names is None:
-            raise ValueError("Coordinate %s has no MultiIndex" % self.name)
+            raise ValueError("IndexVariable %r has no MultiIndex" % self.name)
         index = self.to_index()
         return type(self)(self.dims, index.get_level_values(level), name=level)
 
@@ -1318,7 +1320,7 @@ def assert_unique_multiindex_level_names(variables):
     level_names = defaultdict(list)
     for var_name, var in variables.items():
         if isinstance(var._data, PandasIndexAdapter):
-            idx_level_names = var.to_coord().level_names
+            idx_level_names = var.to_index_variable().level_names
             if idx_level_names is not None:
                 for n in idx_level_names:
                     level_names[n].append('%r (%s)' % (n, var_name))