[ccp4bb] XDS to MTZ for SOLVE

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CCP4bb <-- 2007 <-- March 2007 <-- 07 March 2007

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Subject: Re: Very weird
From: Edwin Pozharski epozh001 {- at -} UMARYLAND {- dot -} EDU
Date: 2007-03-07

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Subject: Re: XDS to MTZ for SOLVE
From: "Winter, G (Graeme)" g {- dot -} winter {- at -} DL {- dot -} AC {- dot -} UK
Date: 2007-03-07

Subject: XDS to MTZ for SOLVE
From: "Santarsiero, Bernard D {- dot -} " bds {- at -} UIC {- dot -} EDU
Date: 2007-03-07

Not purely a ccp4 question, but an MTZ file is involved, so stick with me.

I've collected a SAD data set, and processed with XDS. I can use XDSCONV
to generate an MTZ, SHELX, and CNS file. I chose the MTZ file since it
keeps the intensities. SHELX does too (the F**2), but has separate lines
for (h,k,l) and (-h,-k,-l). The MTZ file has hkl,IMEAN, SIGIMEAN, I+,
SIGI+, I-, SIGI-.

I used mtzdump (or could use MTZVARIOUS) to convert this file to a simple
ASCII file, and then extracted just the hkl, I+, SIGI+, I-, SIGI-. Since
CCP4 fills in all of the reflections in an ASU, I removed those reflection
entries with SIGIMEAN = -999.0.

I have a file with has some entries with -999 (for the non-measured
value), especially those in the centric zones.

For SOLVE, does it identify entries with a value of -999 as a placeholder,
or should I entirely removed those from the data file? I used the options

PREMERGED
READFORMATTED
READ_INTENSITIES

in SOLVE. What if I measured I- but I+? That's why I left them all in.

Suggestions on what is best for the solve run? I'm concerned that it's
interpretting the -999 as a real measurement.

Bernie Santarsiero

CCP4bb navigation

CCP4bb <-- 2007 <-- March 2007 <-- 07 March 2007

Previous message:
Subject: Re: Very weird
From: Edwin Pozharski epozh001 {- at -} UMARYLAND {- dot -} EDU
Date: 2007-03-07

Next message:
Subject: Re: XDS to MTZ for SOLVE
From: "Winter, G (Graeme)" g {- dot -} winter {- at -} DL {- dot -} AC {- dot -} UK
Date: 2007-03-07