[ccp4bb] difference between I over sigma I and I over sd

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CCP4bb <-- 2008 <-- January 2008 <-- 19 January 2008

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Subject: Re: How to refine a structure with ATP and AMP and pyrophosphate sharing the same density in CCP4i?
From: Pietro Roversi pietro {- dot -} roversi {- at -} PATH {- dot -} OX {- dot -} AC {- dot -} UK
Date: 2008-01-18

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Subject: Calculate dipole moment of ligands from their coordinates
From: Zheng Zhou zhengzhouzz {- at -} GMAIL {- dot -} COM
Date: 2008-01-19

Subject: difference between I over sigma I and I over sd
From: Lu Yongzhi luyongzhi99 {- at -} 163 {- dot -} COM
Date: 2008-01-19

Hi everyone,

When I scale the data using Scala, I don't know differences between
_diffrn_reflns.meanI_over_sigI_all 6.5475
_diffrn_reflns.meanI_over_sd_all 21.3013
in the statistics. I think that both "sigma" and "sd" have the same meaning--"standard deviation". By the way, in the file header of PDB's, what are the meanings of the numbers 5 and 1 in the row "HELIX", numbers 0, 1 and -1 in the row "SHEET". And in the row "SHEET", what's the meaning of the last 6 columns.
HELIX 1 1 THR A 35 ASP A 37 5 3
HELIX 2 2 SER A 41 TYR A 46 1 6
HELIX 3 3 GLU A 68 ALA A 82 1 15 SHEET 1 C 6 GLU A 224 ARG A 232 0
SHEET 2 C 6 ILE A 214 GLU A 221 -1 N CYS A 217 O ARG A 229
SHEET 3 C 6 PHE A 183 VAL A 189 -1 N PHE A 187 O LEU A 218
SHEET 4 C 6 VAL A 302 LEU A 309 -1 O ILE A 306 N LYS A 184
SHEET 5 C 6 LYS A 254 HIS A 261 -1 N ILE A 258 O GLY A 305
SHEET 6 C 6 GLU A 280 PRO A 288 1 O ASP A 283 N VAL A 257

Thanks

Lu Yongzhi

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CCP4bb <-- 2008 <-- January 2008 <-- 19 January 2008

Next message:
Subject: Calculate dipole moment of ligands from their coordinates
From: Zheng Zhou zhengzhouzz {- at -} GMAIL {- dot -} COM
Date: 2008-01-19