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Re: performing multiple histograms without loops [message #69610]

Thu, 04 February 2010 11:21

Jeremy Bailin
Messages: 618
Registered: April 2008

Senior Member

On Feb 4, 7:05 am, chris <rog...@googlemail.com> wrote:
> Hi,
> maybe you can speed up your vectorized approach by avoding the
> transpose step and by using the SAMPLE keyword within rebin to:
> rebin(ul64lindgen(1,ndatasets)*dataspan,size.... ,/SAMPLE) For large
> vectors (replicate( { : } )).(0) may work sometimes faster.
>
> Greets
>
> CR

Indeed! Changing the rebin makes a huge difference... for example,
with ndatasets=10000000, datalen=10, datarange=100, I get a factor of
3 improvement.

10000000 10 100 11.5 9.1

turns into

10000000 10 100 11.6 3.2

I didn't try the full grid of parameters, but if that's consistent
across the board, that brings the vectorized approach up to at least
as good as the loop approach over almost the entire grid, and quite a
bit better over most of it.

-Jeremy.

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[Message index]

		Re: performing multiple histograms without loops By: Jeremy Bailin on Thu, 04 February 2010 11:21
		Re: performing multiple histograms without loops By: rogass on Thu, 04 February 2010 04:05
		Re: performing multiple histograms without loops By: JDS on Wed, 03 February 2010 13:47
		Re: performing multiple histograms without loops By: Jeremy Bailin on Wed, 03 February 2010 06:12
		Re: performing multiple histograms without loops By: Jeremy Bailin on Wed, 03 February 2010 05:43
		Re: performing multiple histograms without loops By: Wout De Nolf on Tue, 02 February 2010 02:11
		Re: performing multiple histograms without loops By: MC on Tue, 02 February 2010 01:48

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