Fig8.4n <- function()
{
#  postscript("Fig8.4.ps", height = 3.9, width = 6.5, horiz = F)
  par(mar = c(1.5, 2.5, 1.5, 0.5), mgp = c(1.5, 0.4, 0))
  y <- c(rep(0, 512), rep(1, 512 * 2), rep(0, 512))
  ywd <- wd(y, filter.number = 5)
  plot((1:32)/32, extract(ywd, klev = 5), ylab = "Coefficient values")
  lines((1:32)/32, rep(0, 32), lty = 2)
#  graphics.off()
  NULL
}