PeakAddRemove

Peak Addition/Removal Settings

If the peak list is being edited during fitting, then four functions are used to modify the list, one which adds peaks to badly fit regions, one which removes peaks that do not significantly improve the fit, one which splits single peaks into multiple peaks, and one which combines pairs of peaks into single peaks. Decisions to add, remove, or split peaks is determined based on whether or not noise exceeds a given cutoff, specified by ‘par.cutoff’. Decisions to combine peaks are determined by calculating whether peak combination raises the noise level less than is expected from removing a noise peak. The parameter giving the relative expected change is the noise per peak, given in ‘par.npp’.

At each step of peak addition, add, remove, split, and combine functions may be run. By default, none of these run after the last fit optimization (such that peaks are not added or removed without another chance to optimize parameters), and only remove and combine functions run immediately before the last fit optimization. Otherwise, all functions run. However, the user may take full control over which functions run at each step in the ‘par.control’ field.

The final option in peak addition is the sign of peaks. Peaks may be all positive, all negative, or both. This is determined in the ‘par.sign’ field (‘+’,’–‘,’+–‘).