Methods working in this way represent an alternative to the derivative method used for peak position hunting.
A by-product is of course the intensity.

Taupin (1973),
Huang and Parrish (1975),
Will, Sonneveld and Visser (1975).
Some programs are still in use.

The main problem of this kind of software is how to make the decision without error about the number of peaks to be included in a compact block of overlapping peaks.

These methods refine the position, the intensity, the width and possibly several profile parameters for each reflection.

The use of these methods should be limited to simple cases, possibly to the estimation of peak positions at low angle for indexation purposes.
 

The ultimate evolution of these programs has been to make a list of the starting positions for the peaks to be hunted by using the cell parameters. These softwares are now very similar to those of the next chapter.