Re: best cumulative sum


Michael Spencer wrote:
> David Isaac wrote:
> for a solution when these are available.
> > Something like:
> > def cumreduce(func, seq, init = None):
> > """Return list of cumulative reductions.
> >
> >
> This can be written more concisely as a generator:
>
> >>> import operator
> >>> def ireduce(func, iterable, init):
> ... for i in iterable:
> ... init = func(init, i)
> ... yield init
> ...
> >>> list(ireduce(operator.mul, range(1,5),init=1))
> [1, 2, 6, 24]
> >>>
If iterable has no elements, I believe the behaviour should be [init],
there is also the case of init=None that needs to be handled. But
otherwise, that is more or less what I wrote for my scanl/scanl1.

> Michael

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