to_cns w1.sca w1.hkl [< 1 second]
to_cns w2.sca w2.hkl [< 1 second]
to_cns w3.sca w3.hkl [< 1 second]
to_cns w4.sca w4.hkl [< 1 second]
The information for each wavelength is then merged into a single reflection file, at the same time giving each wavelength a unique name (eg. f_w1, f_w2, f_w3, f_w4). The merge and renaming are performed with the CNS task file merge.inp.
cns_solve < merge.inp > merge.out [28 seconds]
The output of the merge.inp task file is a CNS formatted reflection file. This will contain a header which describes the data items in the file, followed by the data items themselves. The file is plain ASCII and can be viewed with any text viewer/editor. Example header from a CNS reflection file contained multiple data sets for MAD phasing:
NREFlection= 25778
ANOMalous=TRUE { equiv. to HERMitian=FALSe}
DECLare NAME=F_W1 DOMAin=RECIprocal TYPE=REAL END
DECLare NAME=S_W1 DOMAin=RECIprocal TYPE=REAL END
DECLare NAME=F_W2 DOMAin=RECIprocal TYPE=REAL END
DECLare NAME=S_W2 DOMAin=RECIprocal TYPE=REAL END
DECLare NAME=F_W3 DOMAin=RECIprocal TYPE=REAL END
DECLare NAME=S_W3 DOMAin=RECIprocal TYPE=REAL END
DECLare NAME=F_W4 DOMAin=RECIprocal TYPE=REAL END
DECLare NAME=S_W4 DOMAin=RECIprocal TYPE=REAL END
INDE 5 0 -18 F_W1= 50.523 S_W1= 19.283 F_W2= 26.342
S_W2= 16.583 F_W3= 33.696 S_W3= 18.656
F_W4= 0.000 S_W4= 0.000
INDE 6 0 -18 F_W1= 53.028 S_W1= 18.030 F_W2= 1.929
S_W2= 1.929 F_W3= 22.004 S_W3= 15.993
F_W4= 0.000 S_W4= 0.000
INDE 7 0 -18 F_W1= 34.201 S_W1= 34.201 F_W2= 0.000
S_W2= 0.000 F_W3= 6.684 S_W3= 6.684
F_W4= 0.000 S_W4= 0.000
After merging of the wavelength information the datasets must be scaled together (assuming that this has not been done in some other way prior to entering CNS). The scaling is performed with the CNS task file scale.inp.
cns_solve < scale.inp > scale.out [24 seconds]
In this case the data extends to high enough resolution to perform Wilson scaling on the reference wavelength, to which the other wavelengths will then be scaled. The Wilson scaling will place the data on an approximate absolute scale.
Script to run this tutorial