train <- read.table("loans.dat",header=F,col.names=c("x1","x2","y"));

X <- cbind(train$x1,train$x2);
y <- (train$y==1);

size   <- 100;
circle <- mat.or.vec(size,2);
center <- c(0.359,0.482);
radius <- 0.056;
for (i in 1:size) {
  s <- 6.28*i/(size-1);
  circle[i,1] = center[1]+radius*sin(s);
  circle[i,2] = center[2]+radius*cos(s); 
}  

source("psopts.r");
ps.options(width=5.0,height=5.0);
postscript(file="near00.eps");

lim <- c(0.2,0.6);
plot(X,type='n',xlim=lim,ylim=lim,xlab="FICO Score",ylab="P-Index");
points(X[y,],pch='o',col="red");
points(X[!y,],pch='o',col="green");
points(center[1],center[2],pch='+',col="black");
lines(circle);
dev.off();