Re: [ccp4bb] Definition of Fourier coefficients

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

Previous message:
Subject: Missing space group in ?.mtz file
From: Petr Kolenko kolenko {- at -} IMC {- dot -} CAS {- dot -} CZ
Date: 2008-07-08

Next message:
Subject: Re: Missing space group in ?.mtz file
From: Eleanor Dodson ccp4 {- at -} YSBL {- dot -} YORK {- dot -} AC {- dot -} UK
Date: 2008-07-08

Subject: Re: Definition of Fourier coefficients
From: Kevin Cowtan cowtan {- at -} YSBL {- dot -} YORK {- dot -} AC {- dot -} UK
Date: 2008-07-08

Yup, refmac too.

Pavel Afonine wrote:
> Not sure for other software, but in phenix.refine you can request to
> output I*mFo-J*DFc map, where I and J are any user specified values.
>
> Pavel.
>
>
> On 7/7/2008 6:00 PM, Meyer, Peter wrote:
>> It is redundant, but it adds an additional step if someone wanted to
>> calculate something like a 3mFO-2DFc map.
>>
>> Thanks,
>>
>> Pete
>>
>> -----Original Message-----
>> From: Kevin Cowtan [mailto:cowtan@ysbl.york.ac.uk]
>> Sent: Mon 7/7/2008 10:18 AM
>> To: Meyer, Peter
>> Cc: CCP4BB@jiscmail.ac.uk
>> Subject: Re: [ccp4bb] Definition of Fourier coefficients
>>
>> Probably because in the classic implementation it is redundant, D
>> being derived directly from sigmaa.
>>
>> Some programs refine D and sigmaa (or equivalent terms, such as
>> Lunin's alpha and beta) separately. This is conceptually equivalent to
>> deriving D from sigmaa and refining the scale between Fo and Fc
>> simultaneously with sigmaa.
>>
>> Kevin
>>
>>
>> Meyer, Peter wrote:
>>
>>> Slightly off-topic from the original question, but is there a reason
>>> that most programs don't output D for sigma_a coefficients?
>>>
>>> Pete
>>>
>>>
>>> -----Original Message-----
>>> From: CCP4 bulletin board on behalf of Mayer, Mark (NIH/NICHD) [E]
>>> Sent: Sat 7/5/2008 2:39 PM
>>> To: CCP4BB@JISCMAIL.AC.UK
>>> Subject: [ccp4bb] Definition of Fourier coefficients
>>>
>>> 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
>>>
>>>
>>>
>>>
>
>

CCP4bb navigation

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

Previous message:
Subject: Missing space group in ?.mtz file
From: Petr Kolenko kolenko {- at -} IMC {- dot -} CAS {- dot -} CZ
Date: 2008-07-08

Next message:
Subject: Re: Missing space group in ?.mtz file
From: Eleanor Dodson ccp4 {- at -} YSBL {- dot -} YORK {- dot -} AC {- dot -} UK
Date: 2008-07-08