Example: Merging Crystallographic Reflection Files

The xrefin write statement allows one to merge reflection information. However, no relative scaling is performed. The following example shows how information can be merged. Suppose that reflection file “r.1" contains the following information:
index 1 2 3 fobs 40. phase 90. fom 0.5 
index 2 3 4 fobs 30. phase 60. fom 0.4  weight 1.4
index 3 4 5 fobs 20. phase 50. fom 0.3
index -1 -2 -3 fobs 40. phase 90. fom 0.5   sigma 4.0
index -2 -3 -4 fobs 30. phase 60. fom 0.4
index -3 -4 -5 fobs 20. phase 50. fom 0.3
and reflection file “r.2" contains
index 1 2 3   fcalc 3. 3.5 fpart 4. 4.5 sigma 3.0
index -1 2 -5 fobs 20. fcalc 4. 4.5 weight 3.0
Merging of the two files can then be accomplished by using the following statements:
xrefin
  nreflection=100
  reflection @r.1 end
  reflection @r.2 end
  write reflection fobs fcalc output=merge.dat end
end
The resulting file “merge.dat" will contain the following information:
index 1 2 3 fobs 40. phase 90. fom 0.5  fcalc 3. 3.5 fpart 4. 4.5 sigma 3.0
index 2 3 4 fobs 30. phase 60. fom 0.4  weight 1.4
index 3 4 5 fobs 20. phase 50. fom 0.3
index -1 -2 -3 fobs 40. phase 90. fom 0.5   sigma 4.0
index -2 -3 -4 fobs 30. phase 60. fom 0.4
index -3 -4 -5 fobs 20. phase 50. fom 0.3
index -1 2 -5 fobs 20. fcalc 4. 4.5 weight 3.0

Note that reflection 1,2,3 is already present in the first file. Information has been merged for this reflection.



Xplor-NIH 2023-11-10