npstreams.preduce

npstreams.preduce(func, iterable, args=None, kwargs=None, processes=1, ntotal=None)

Parallel application of the reduce function, with keyword arguments.

Parameters:

• func (callable) – Function to be applied to every element of iterable.
• iterable (iterable) – Iterable of items to be reduced. Generators are consumed.
• args (tuple or None, optional) – Positional arguments of function.
• kwargs (dictionary or None, optional) – Keyword arguments of function.
• processes (int or None, optional) – Number of processes to use. If None, maximal number of processes is used. Default is one.
• ntotal (int or None, optional) – If the length of iterable is known, but passing iterable as a list would take too much memory, the total length ntotal can be specified. This allows for preduce to chunk better.

Returns:

reduced

Return type:

object

Notes

If processes is 1, preduce is equivalent to functools.reduce with the added benefit of using args and kwargs, but initializer is not supported.