e_rnorm(200)
x_runif(200)
y_sin(2+pi*(1-x)*2)+x*e


plot(x,y)

lines(loess.smooth(x,y),lty=1,col=3)
lines(ksmooth(x,y),lty=2,col=4)
lines(smooth.spline(x,y),lty=3,col=5)
legend(0,2,c("locally weighted","kernal smooth","spline smooth"),lty=1:3,col=3:5)