PHONYD: Generate Idealized Intensity Data
Author: Jim Stewart, Department of Chemistry,
University of Maryland, College Park, MD 20742, USA
PHONYD generates a set of ideal "observed" structure factor amplitudes from
calculated structure factor amplitudes, for purposes of testing programs.
Optionally, the idealized data may be generated with random errors.
The reflection data in the input archive data bdf is read. Three quantities
must be available: h,k,l, Frel (IDnum n304) and Fcal (IDnum n800). Frel will be
replaced on the output bdf and if the input bdf contains I, σI and
σF, these items will also be replaced. If I and σI are to be
replaced, each reflection record must contain 1/Lp. In addition the absorption
factor will be applied if it is in the file. For each reflection, a random
number is generated from a Gaussian population with a mean of 0. and a standard
deviation of 1.0. This random number is multiplied by a specified error to
modify the 'perfect' F(cal) values.
Frel = Fcal * (1. + ERROR * RANNUM) / SCALE
I rel = Lp / ABSORP
Reads reflection data from the input archive bdf
Writes idealized reflection data to the output archive bdf
PHONYD sca .53 lst 1000 err 0.01
Frel and Irel values are replaced by values derived from Fcal. The new values
will have an R value of 0.01 and will have an F(rel) scale factor of .53.
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