### target region
PLOC= list(LON=c(138.3152, 139.0214),
LAT=c(35.09047, 35.57324))
PLOC$x =PLOC$LON
PLOC$y =PLOC$LAT
#### set up projection
PROJ = setPROJ(type=2, LAT0=mean(PLOC$y) , LON0=mean(PLOC$x) )
perim= getGEOperim(PLOC$LON, PLOC$LAT, PROJ, 50)
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