Method __array_finalize__

zipline/lib/labelarray.py:269–306

Called by Numpy after array construction. There are three cases where this can happen: 1. Someone tries to directly construct a new array by doing:: >>> ndarray.__new__(LabelArray, ...) # doctest: +SKIP In this case, obj will be None. We treat th

(self, obj)

        return value in self.reverse_categories

    def __array_finalize__(self, obj):
        """
        Called by Numpy after array construction.

        There are three cases where this can happen:

        1. Someone tries to directly construct a new array by doing::

            >>> ndarray.__new__(LabelArray, ...)  # doctest: +SKIP

           In this case, obj will be None.  We treat this as an error case and
           fail.

        2. Someone (most likely our own __new__) does::

           >>> other_array.view(type=LabelArray)  # doctest: +SKIP

           In this case, `self` will be the new LabelArray instance, and
           ``obj` will be the array on which ``view`` is being called.

           The caller of ``obj.view`` is responsible for setting category
           metadata on ``self`` after we exit.

        3. Someone creates a new LabelArray by slicing an existing one.

           In this case, ``obj`` will be the original LabelArray.  We're
           responsible for copying over the parent array's category metadata.
        """
        if obj is None:
            raise TypeError(
                "Direct construction of LabelArrays is not supported."
            )

        # See docstring for an explanation of when these will or will not be
        # set.
        self._categories = getattr(obj, 'categories', None)
        self._reverse_categories = getattr(obj, 'reverse_categories', None)
        self._missing_value = getattr(obj, 'missing_value', None)

    def as_int_array(self):
        """