The method 1, wherein {HEAD ~ the compensation voltage} is determined by calculating a difference between the value of the at least one parameter and a fixed stored value and determining {TAIL ~ the compensation voltage} from a stored relationship of differences to compensation voltages 
is determined by determining
The method 1 , wherein { HEAD ~ the compensation voltage } is determined by calculating a difference between the value of the at least one parameter and a fixed stored value and determining { TAIL ~ the compensation voltage } from a stored relationship of differences to compensation voltages
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH