Re: [ccp4bb] Phase matching program(s)

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CCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999

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From: Eleanor Dodson ccp4 {- at -} YSBL {- dot -} YORK {- dot -} AC {- dot -} UK
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Subject: Re: Phase matching program(s)
From: Eleanor Dodson ccp4 {- at -} YSBL {- dot -} YORK {- dot -} AC {- dot -} UK
Date: 2009-08-03

I cant answer for cphasematch but I believe it uses a resolution
dependent phase analysis discussed by Woolfson and Lunin in the 1980s
and similar to the method used to calculate the MAPCC used in SHELXE

That checks for a possible origin shift as well as analysing
difference - but I presume you have no origin shift?

PHISTATS documentation describes what it does:
First phase differences are corrected for differences of nPI to always
lie between -180 and +180

It outputs:

CC of phase_diff with W1 and W2
CC of cos(phi_diff) with W1 and W2

Eleanor

1) James Tucker Swindell II wrote:
> I am currently working with two of ccp4i's phase comparison software
> packages, Phase Comparison(a clipper utility) and Phistats. I am
> having a problem finding information concerning both how the programs
> actaully analyze the data (since I find slightly different results
> with each program) and finding documentation concerning the labeling
> of the columns in the output log files.
>
> In Phase Comparison I am using phase/weight(phi/tom)
>
> In Phistat I am using
> PHIBP = PHIC WP = FOM
> PHIB2 = PHIB. W2 = FOMM
>
> Both results are very close buy I am intersted in what algorithmis
> being used in each, perhaps not to technical but enough to truly
> understand what each program is doing and it's corresponding output.
>
> Any assistance would be appreciated
>
> James Tucker Swindell II
> Ph.D. Candidate, Physics
> Research:
> Department of Biochemistry and Molecular Biology
> University of Georgia
> B202 Davison Life Sciences Bldg.
> 1057 East Green St.
> Athens Ga, 30605
> Lab: 1(706)-542-2913
> Direct: 1(706)-247-5220
> Fax: 1(706)-542-3077
> jtswinde@seceg.uga.edu
>
>

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CCP4bb <-- 1999 <-- November 1999 <-- 30 November 1999

Previous message:
Subject: Re: Density modification
From: Eleanor Dodson ccp4 {- at -} YSBL {- dot -} YORK {- dot -} AC {- dot -} UK
Date: 2009-08-03

Next message:
Subject: Re: question of extra high B factor
From: Eleanor Dodson ccp4 {- at -} YSBL {- dot -} YORK {- dot -} AC {- dot -} UK
Date: 2009-08-03