enhanced s.sample

Simon Cox simon at ned.dem.csiro.au
Fri Jan 10 10:23:14 EST 1997

I have posted an enhanced version of Darrell McCauley's 
s.sample program at 


The enhancements are all concerned with performance.  
We have improved memory management, by buffering the rows 
of the source raster so that the number of reads from disk is 
reduced.  This is an advantage if you are processing a large 
number of target sites, and particularly if they are already 
sorted approximately according to northing.  A flag also allows 
you to load the whole raster into memory at once, but this is 
rarely worthwhile.  

The motivation for these changes is that I use s.sample to do 
the interpolation in my version of r.proj.  I found that 
s.sample was the rate controlling step.  The enhancements have 
decreased the run-time for large maps from *days* to *minutes* 
so appear to be worthwhile!!!

Simon Cox  (and Ian Brayshaw - who did the coding).  
Dr Simon Cox - Australian Geodynamics Cooperative Research Centre
CSIRO Exploration & Mining,  PO Box 437,  Nedlands, WA 6009 Australia
T:  +61 9 389 8421    F:  +61 9 389 1906   simon at ned.dem.csiro.au

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