& xx_obcsestartdate1, xx_obcsestartdate2, xx_obcseperiod,
& , xx_obcseperiod
_RL xx_obcseperiod
I xx_obcsestartdate, xx_obcseperiod,
fldperiod = xx_obcseperiod
startrec = int((modelstart - diffsecs)/xx_obcseperiod) + 1
endrec = int((modelend - diffsecs)/xx_obcseperiod) + 2
xx_obcseperiod = 0. _d 0