#  TO DRAW POSTERIOR W/SHADING > 0:

par(lwd=1.5,cex=1.5,mar=c(5,4,1,1))

y <- dnorm(x,postmean,postsd)
plot(x,y,type="l",
  xlab=as.expression(as.name('theta')),ylab="density",cex=1.5)
polygon(c(x[x>=0],rev(x[x>=0])),
  c(y[x>=0],rep(0,length(y[x>=0]))),
  lty=1,col='blue',density=10,angle=45,border=NA)
lines(0,y[x==0], type = "h", col = "blue", lwd=3)
abline(h=0)