def intersection(self, other):
"""
Form the intersection of two Index objects. Sortedness of the result is
not guaranteed
Parameters
----------
other : Index or array-like
Returns
-------
intersection : Index
"""
if not hasattr(other, "__iter__"):
raise Exception("Input must be iterable!")
if self.equals(other):
return self
other = _ensure_index(other)
if other.dtype != np.object_:
other = other.astype(object)
if self.is_monotonic and other.is_monotonic:
return Index(lib.inner_join_indexer_object(self, other)[0])
else:
indexer = self.get_indexer(other)
indexer = indexer.take((indexer != -1).nonzero()[0])
return self.take(indexer)
def _join_monotonic(self, other, how='left', return_indexers=False):
this_vals = self.values
if self.dtype != other.dtype:
other = Index(other, dtype=object)
other_vals = other.values
if how == 'left':
join_index = self
lidx = None
ridx = lib.left_join_indexer_object(self, other)
elif how == 'right':
join_index = other
lidx = lib.left_join_indexer_object(other, self)
ridx = None
elif how == 'inner':
join_index, lidx, ridx = lib.inner_join_indexer_object(this_vals,
other_vals)
join_index = self._wrap_joined_index(join_index, other)
elif how == 'outer':
join_index, lidx, ridx = lib.outer_join_indexer_object(this_vals,
other_vals)
join_index = self._wrap_joined_index(join_index, other)
else: # pragma: no cover
raise Exception('do not recognize join method %s' % how)
if return_indexers:
return join_index, lidx, ridx
else:
return join_index
def _join_monotonic(self, other, how="left", return_indexers=False):
if how == "left":
join_index = self
lidx = None
ridx = lib.left_join_indexer_object(self, other)
elif how == "right":
join_index = other
lidx = lib.left_join_indexer_object(other, self)
ridx = None
elif how == "inner":
join_index, lidx, ridx = lib.inner_join_indexer_object(self, other)
join_index = Index(join_index)
elif how == "outer":
join_index, lidx, ridx = lib.outer_join_indexer_object(self, other)
join_index = Index(join_index)
else: # pragma: no cover
raise Exception("do not recognize join method %s" % how)
if return_indexers:
return join_index, lidx, ridx
else:
return join_index
