dat<-read.csv(file="in.txt",header=F)

end<-"end"
a<-1
for (a in 1:length(dat$V1)){

lab<-dat[a:a,1:1]
xc<-dat[a:a,2:2]
yc<-dat[a:a,3:3]
d<-16
r<-10
i<-1
fn=paste("out",a,".txt",sep="")

beta=(360/d)/2 # calculate the degrees for half a slice 

  for (i in 1:d ){
  id<-paste(lab,i,sep="")
  theta=i*(beta*2) - beta # find the center of this slice

    #change degrees to radians
    dbeta=beta*0.017453292   # size of half slice - bc needs
    angle=theta*0.017453292  # center of slice - bc needs

    x1=xc
    y1=yc

    # intersction of tangent line and extended radius (lower)
    x2=x1 + r*sin(angle) +r*(sin(dbeta)/cos(dbeta))*sin(1.570796327 +angle)
    y2=y1 + r*cos(angle) +r*(sin(dbeta)/cos(dbeta))*cos(1.570796327 + angle)

    # intersction of tangent line and extended radius (upper)
    x3=x1 + r*sin(angle) + r*(sin(dbeta)/cos(dbeta))*sin(1.570796327 + 3.1415927 + angle)
    y3=y1 + r*cos(angle) + r*(sin(dbeta)/cos(dbeta))*cos(1.570796327 + 3.1415927 + angle)

    # create a text file that describes the triangle area for r.in.poly
    out1<-c(x1,y1)
    out1t<-t(out1)
    out2<-c(x2,y2)
    out2t<-t(out2)
    out3<-c(x3,y3)
    out3t<-t(out3)
if (i==1){
write.table(id, file= fn,append=F, quote=F, sep=",",row.names=F,col.names=F)
}else{
write.table(id, file= fn,append=T, quote=F, sep=",",row.names=F,col.names=F)
}
write.table(out1t, file= fn,append=T, quote=F, sep=",",row.names=F,col.names=F)
write.table(out2t, file= fn,append=T, quote=F, sep=",",row.names=F,col.names=F)
write.table(out3t, file= fn,append=T, quote=F, sep=",",row.names=F,col.names=F)
write.table(end, file= fn,append=T, quote=F, sep=",",row.names=F,col.names=F)


i<-i+1
}
a<-a+1
}