Reduce this object’s data windows by applying var along its dimension.
Parameters
keep_attrs (bool, default: None) – If True, the attributes (attrs) will be copied from the original
object to the new one. If False, the new object will be returned
without attributes. If None uses the global default.
**kwargs (dict) – Additional keyword arguments passed on to var.
Returns
reduced (sametypeascaller) – New object with var applied along its rolling dimension.