the data set for this circle was constructed with the following command line:

for var in {0,1,2,3}{0,12,,4,,6,,8,9}{0,12,,4,,6,,8,}; do (echo -e "scale=5;(c($var*0.017453293)*300)"+300| bc -l ) ;echo -n ","; (echo -e "scale=5;(s($var*0.01753293)*300)+300"|bc -l ) ;echo -n " " ;done;

this page evolved from this.