The evaluated value {HEAD ~ Smn=Mm×} is calculated from a plurality of different write power compensated values Pcn , {TAIL ~ the write power} Pwm, and the modulation Mm 
is calculated from
The evaluated value { HEAD ~ Smn = Mm× } is calculated from a plurality of different write power compensated values Pcn , { TAIL ~ the write power } Pwm , and the modulation Mm
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH