... In the present case this can take values `MEAN' or `MEDIAN'. ... The average of each attitude component (ie RA, dec and apos) is calculated as either the mean or the median (depending on the value of withmedianpnt ) of all the successful values. attsource =`atthk': in this case the time samples are obtained from the atthk file ( atthkset ), therefore are expected to be uniform; however the averages of these values have already been calculated and are present as keywords. ...