##produce some plots for the lecture

source("xy.R")

plotxy(pt2)

text(Xpos(pt2)-.1, Ypos(pt2)-.1, paste("x=", round(Xpos(pt2),3)), adj=0)

text(Xpos(pt2)-.1, Ypos(pt2)+.1, paste("y=", round(Ypos(pt2),3)), adj=0)

text(1, .1, substitute(list(theta) == x, list(x=round(Ypos(pt2),3))), adj=0)

par(srt=45)
text(1,.7, paste("r = ", Rval.rt(pt2)))
par(srt=0)

lines(c(0,Xpos(pt2)), c(0,Ypos(pt2)), lty=3)