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Re: [ccp4bb]: pksearch

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aaah, i smell flame-bait !

> Here probably another case of foot in mouth disease
> regarding peaksearch..... Consider:

okay, let me rain on your parade a tad:

>    if (fmap(i,ii,iii).ge.maxval(fmap(i-m:i+m,ii-m:ii+m,iii-m:iii+m))) then
>      print*, fmap(i,ii,iii), i,ii,iii ! or put in peak list for sorting
> whatever
>    end if

in the pathetic case that the entire map is zero (or some other arbitrary
constant), you will find that *every* point in the map is a "peak"; in
general, every local plateau will yield one or more peaks; also, you might
want to introduce an absolute threshold and test that fmap(..) actually
exceeds that

> Note:
> a) can be used at any dimension (n)

..... but does require separate code (different nr of indices in array and
different nr of nested loops)

> b) can be used with larger search vortex (m) (think noise)

why ? all this does is force individual peaks to have a certain minimum
separation > 1 grid point. in coarse, low-resolution maps (think pattersons)
this may well have unwanted side-effects

> c) beats coding (2m+1)**n if-statements

but the explicit case requires only [(2m+1)**n]-1 IF statements ;-) and you
could replace them by three nested DO-loops with just two IF statements inside

> d) is fast.

..... "to every complex problem, there is fast, easy-to-comprehend, wrong
solution" :-)

all in all: a B for effort

--dvd

******************************************************************
                        Gerard J.  Kleywegt
    [Research Fellow of the Royal  Swedish Academy of Sciences]
Dept. of Cell & Molecular Biology  University of Uppsala
                Biomedical Centre  Box 596
                SE-751 24 Uppsala  SWEDEN

    http://xray.bmc.uu.se/gerard/  mailto:gerard@xray.bmc.uu.se
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