An interesting problem

McGlinchy, Alistair Alistair.McGlinchy at
Wed Jan 3 22:56:17 GMT 2007

> I think that the previous mention of a 2D autocorrelation will be  
> good to explore, but you can use the "moving average" trick to avoid  
> lots of extra cycles while summing neighborhoods.  I've implemented  
> this in C before and gotten speedups of 1x to 50x, depending on the  
> neighborhood size.

Aye, That's the trick. Run time from 10 mins to 16secs for the 30x100
case. Great fun!

Code available if anyone else was interested.



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