Calculate the sum of weights, accounting for missing values in the data.
Parameters:
dim (str or sequence of str, optional) – Dimension(s) over which to sum the weights.
keep_attrs (bool, optional) – If True, the attributes (attrs) will be copied from the original
object to the new one. If False (default), the new object will be
returned without attributes.
Returns:
reduced (Dataset) – New Dataset object with the sum of the weights over the given dimension.
