#----------------------------------------------------------------------
# Draw normal distribution with filled polygon

filled.normal <- function(from=-5,to=5, mean, sd_gor, 
  hatch.from=-5, hatch.to=1.5, col='red', angle=45, density=NULL)  {

# history, density plot
	x = c(seq(from, to, length=50)) #, c(hatch.to, hatch.from))
	y = dnorm(x, mean=mean, sd=sd_gor)
	plot(x, y, from=from, to=to, type='l')


# colored polygon
    xp = seq(hatch.from, hatch.to, length=50)
    yp = dnorm(xp, mean=mean, sd=sd_gor)

    # close the polygon
    xp = c(xp, hatch.to, hatch.from)
    yp = c(yp, 0., 0.)

	polygon(xp,yp, col='red', border="blue") #, density=density)

    # black horizontal line on x-axis
    xl = c(from, to)
    yl = c(0, 0)
    lines(xl,yl)
}
filled.normal(mean=3, sd_gor=1, from=-5, to=10)
#----------------------------------------------------------------------
filled.rejection.normal <- function(from=-5,to=5, mean, sd, 
  confidence=.95, col='red', angle=45, density=5)  {

	plot(dnorm, from=from, to=to)
	polygon(c(from,to),c(0,0))

    rej = 0.5*(1-confidence)
	xleft = qnorm(rej)
	hatch.from = from
	hatch.to = xleft
	xp = c(seq(hatch.from,hatch.to,(hatch.to-hatch.from)/50), c(hatch.to, hatch.from))
	yp = c(dnorm(xp)[1:(length(xp)-2)], c(0., 0.))
	# without density argument, I get filled polygon
	polygon(xp,yp, col='red', border="black")

	xright = qnorm(1-rej)
	hatch.from = xright
	hatch.to = to

	xp = c(seq(hatch.from,hatch.to,(hatch.to-hatch.from)/50), c(hatch.to, hatch.from))
	yp = c(dnorm(xp)[1:(length(xp)-2)], c(0., 0.))
	polygon(xp,yp, col='red', border="black")
}
#----------------------------------------------------------------------