Re: [ccp4bb] Definition of Fourier coefficients

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

Previous message:
Subject: Re: Definition of Fourier coefficients
From: Ezra Peisach epeisach {- at -} BU {- dot -} EDU
Date: 2008-07-05

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Subject: Re: Definition of Fourier coefficients
From: Engin Ozkan eozkan {- at -} STANFORD {- dot -} EDU
Date: 2008-07-05

Subject: Re: Definition of Fourier coefficients
From: Pavel Afonine pafonine {- at -} LBL {- dot -} GOV
Date: 2008-07-05

Hi Mark,

for the exact definition look, for example, formula #4 in this paper:
J. Appl. Cryst. (1996). 29, 741-744

For more background look references mentioned there:
(Luzzati, 1953; Main, 1979;Vijayan, 1980; Read, 1986).

Note the essential message in this paper: the values m and D (=alpha)
must be computed using "test" reflections.

This is exactly what implemented in PHENIX (maps output by phenix.refine).

Pavel.

On 7/5/2008 12:39 PM, Mayer, Mark (NIH/NICHD) [E] wrote:
> Hi,
>
> What do m and D indicate in the Fourier coefficients for a 2mFo-DFc map?
>
> I've dug a bit in web and CCP4 doc but not found an explanation, though I'm sure its there.
>
> Thanks,
>
> Mark
>

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

Previous message:
Subject: Re: Definition of Fourier coefficients
From: Ezra Peisach epeisach {- at -} BU {- dot -} EDU
Date: 2008-07-05

Next message:
Subject: Re: Definition of Fourier coefficients
From: Engin Ozkan eozkan {- at -} STANFORD {- dot -} EDU
Date: 2008-07-05