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Calculation of Different R Values

  R values are output separately as single numbers for each classification and separately in intensity shells for each group of spectra. The overall R value is stored in the variable $RNMR.


The following example shows a part of the output file, i.e., the calculated calibration factor and the R value. The intensities are calculated from the coordinates by the calibration statement, and the optimal calibration factor is printed for each classification separately. The R value is printed first for each classification and then for each group broken down in intensity shells.

 RELAx>    calibrate 
 CALIbrate>        quality 0.33  automatic off  reference all  group class 
 CALIbrate>    end 
 RELAX: intensities updated for calibration

             class   N(reference)   N(all)  calibration 
             D300              0        23   .5220E+00
 RELAx>    print threshold -0.1 end      {List all deviations and calculate R.} 
 Class D300: R-factor:    .6594E-01 R.m.s. difference:     .8038E-01
 RELAX: overall R-factor statistics 
             min. int.   max. int.    N   R-factor   r.m.s. diff 
             .2550E+01   .5100E+01    1   .4804E-01   .6302E-01
             .1275E+01   .2550E+01    4   .5346E-01   .8720E-01
             .6375E+00   .1275E+01    4   .4047E-01   .4735E-01
             .3187E+00   .6375E+00    9   .6331E-01   .7320E-01
             .1594E+00   .3187E+00    5   .1292E+00   .1204E+00
             .7969E-01   .1594E+00    4   .5022E-01   .5105E-01
             .0000E+00   .5100E+01   27   .6594E-01   .8038E-01
A local R value can be calculated using the select option in the print statement. The following loop calculates the R value for each residue in the sequence:
    set echo off message off end
    for $id in id (name ca) loop rfac
            selection=(byres(id $id)) 
            threshold 9999 
    end loop rfac
    set echo on message on end

Different types of local R values can be calculated using the atom selection routine. For example, the R value for the region around each residue can be calculated with the around option of the atom selection command (see Section 2.15).

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