flex tries to minimize the total angular ha+dec pointing error. If you wish to ignore the hour and or declination terms you many use the noha and nodec options respectively.
If the telescope already has pointing corrections installed and you wish to update them you can specify the system option which will add the telescope pointing coefficients used by the telescope (and found in columns 5 and 6) before computing the revised values.
You may simulate the effect of pointing errors by entering their fixed values as above (e.g. a1=23.0 a2=-.020 etc.) and adding the keyword phony.
The data may be plotted as a vector field (a bunch of arrows showing the magnitude and direction of the errors) using the XVista xplot. command.
Note: the input data requires the hour angle error to be recorded in shaft angle and not angular units.