Re: [ccp4bb]: averaging

["David J. Schuller" <djs63@cornell.edu>]

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On Thu, 28 Feb 2002, Bernhard Rupp wrote:

> Gokulan and I are stuck with what ought to be a simple procedure (harhar)

>    Density correlation:  0.00000  over      0:  0     0:  0     0:  0
> Mapping density to cell using operator   2
>    Density correlation:  0.00000  over    245:245  -113:***   113:113
> Mapping density to cell using operator   3
>    Density correlation:  0.00000  over    -68:-68  -181:***   175:175
> 
> 
> Obviously, we are doing something wrong.
> Secondly, is there a better way to get consistent NCS matrices from direct
> manipulation
> of the maps?
> and third, Should a mask be made instead of just copying the CNS ncs
> matrices?

I should think a mask would help a lot. NCS matrices only make sense when 
applied to a specified region of space; the matrices and mask work 
together.  your correlation output lines above show that the averaging is 
not being done over a reasonable chunk of space.  if you are using the 
matrices for B->A and B->C, you should also specify a mask covering 
subunit B.

=======================================================================
"Supernaturalism is not, on the whole, friendly to science and technology,
 and there is no use in pretending that it is."  -  L. Sprague de Camp
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                        David J. Schuller
                        modern man in a post-modern world
                        MacCHESS, Cornell University
                        djs63@cornell.edu