x <- c(1, 3, 6, 7)
Midx(x)
Midx(x, incl.zero = TRUE)
Midx(x, incl.zero = TRUE, cumulate = TRUE)
tab <- matrix(c(401,216,221,254,259,169), nrow=2, byrow=TRUE)
b <- barplot(tab, beside = FALSE, horiz=TRUE)
x <- t(apply(tab, 2, Midx, incl.zero=TRUE, cumulate=TRUE))
text(tab, x=x, y=b, col="red")
Run the code above in your browser using DataLab