{% if book.isPdf %}
{% else %}
{% endif %}
Applies an accumulator function over an observable sequence, returning the result of the aggregation as a single element in the result sequence. The specified seed value is used as the initial accumulator value.
For aggregation behavior with incremental intermediate results, see the scan
method.
accumulator
(Function
): An accumulator function to be invoked on each element.[seed]
(Any
): The initial accumulator value.
(Observable
): An observable sequence containing a single element with the final accumulator value.