分岐図

bunki <- function() {
    plot(1, 2, type = "n", xlim = c(2.5, 4), ylim = c(0, 1))
    z <- 0.5
    for (l in seq(2.5, 4, length = 1000)) {
        lst <- NULL
        for (i in 1:100) {
            z <- l * z * (1 - z)
            lst[i] <- z
            points(l, lst[i], pch = ".")
        }
    }
}
bunki()