RG#40: Spine plot

set.seed(123)
myd <- data.frame (grp1 = rep(c("A", "B", "C", "D"), each = 5), grp2 = rep(c("G1", "G2", "G3", "G4", "G5"), 4), yvr1 = rnorm (20, 10,3), yvr2 = rnorm (20, 50,12))


 require(grDevices)

# plotting 
spineplot(grp1 ~ grp2, data = myd, col = c("gray50",  "blue", "green4", "tan", "purple"))

## (dependence on a numerical variable)

spineplot(grp1 ~ yvr1, data=myd)

spineplot(grp1 ~ yvr1, data=myd, breaks = 3, col = c("green1", "green3", "darkgreen"))
spineplot(grp1 ~ yvr1, data=myd,breaks = quantile(myd$yvr1) )