# R script to draw interpolation diagram

png("c:/datasets/interp.png")
plot(NULL, NULL, xlim=c(0.5, 0.9), ylim=c(40, 80), type="n")
points(c(0.6, 0.67, 0.8), c(45, 55.85, 76), pch=16)
lines(c(0.6, 0.8, 0.8, 0.6), c(45, 76, 45, 45))
lines(c(0.67, 0.67), c(45, 55.85), lty=2)
lines(c(0.67, 0.8), c(55.85, 55.85), lty=2)
text(0.6, 43.3, "p=0.6")
text(0.67, 43.3, "p=0.67")
text(0.8, 43.3, "p=0.8")
text(0.57, 45, "x=45")
text(0.83, 45, "x=45")
text(0.61, 55.85, "Solve for x=55.85")
text(0.83, 76, "x=76")
dev.off( )