STDANAL - Analysis of Standard Intensities

STDANAL - Analysis of Standard Intensities


This is an interactive decomposition correction. Three functions are available to model the change in intensity with X-ray exposure time.

  1. Linear least squares fit
  2. Polynomial least squares fit
  3. Interpolation (linear - quadratic - cubic or quartic)

Up to 10 sets of standard intensities may be read in. There is no requirement as to the number of standards in each set. A graphical display is available. The scaling function used to correct the data set is by default a simple mean of the scaling functions for each set of standards. These functions may also be weighted according to the method of Blessing, on the basis of intensity, scattering angles or anisotropic weights. The R(merge) value (on F) is calculated before and after application of the scaling function.

The required files are name.ST, and if a correction is to be applied name.UNC. Both these files are written by the CAD4 processor program XCAD4