filnam<-"JK1-2.xyz"
XX<- read.table(filnam)
print(names(XX))
Xloc<- XX[,2]
Yloc<- XX[,3]
print(summary(XX))
Ilow<-c(1, 102,202,302,402,502)
Ihi<-c(101,201,301,401,501,601)
filcol<-c("red", "green", "blue", "orange", "purple", "grey", "darkgreen")
fillwd<-c(1    ,  2     ,  2    ,  3      ,  2     ,  3      ,  2    )
fillty<-c("solid","solid","solid","solid","solid","solid", "solid")
filnlev<-c(8    , 8     , 8    ,  6      ,  6     ,  6      ,  10    )
plot(Xloc,Yloc, typ='n', main=paste(filnam,'has',6,'groups'))
for (i in 1:6){
     points(Xloc[Ilow[i]:Ihi[i]],Yloc[Ilow[i]:Ihi[i]], col=filcol[i])
	           }
 minX<- min(Xloc); maxX<- max(Xloc); minY<- min(Yloc); maxY<- max(Yloc)
 minX2<- floor(minX/200); maxX2<- floor(maxX/200)
 minY2<- floor(minY/200); maxY2<- floor(maxY/200)
 
 Xser<-200*(minX2:maxX2); Yser<-200*(minY2:maxY2)
 n<- length(Xser)
 for (i in 1:n) {lines(c(Xser[i],Xser[i]), c(minY, maxY), lty='dashed')}
 n<- length(Yser)
 for (i in 1:n) {lines(c(minX, maxX), c(Yser[i],Yser[i]),  lty='dashed')}