```
# NOT RUN {
##-- Simple didactical ecdf example :
x <- rnorm(12)
Fn <- ecdf(x)
Fn # a *function*
Fn(x) # returns the percentiles for x
tt <- seq(-2, 2, by = 0.1)
12 * Fn(tt) # Fn is a 'simple' function {with values k/12}
summary(Fn)
##--> see below for graphics
knots(Fn) # the unique data values {12 of them if there were no ties}
y <- round(rnorm(12), 1); y[3] <- y[1]
Fn12 <- ecdf(y)
Fn12
knots(Fn12) # unique values (always less than 12!)
summary(Fn12)
summary.stepfun(Fn12)
## Advanced: What's inside the function closure?
ls(environment(Fn12))
##[1] "f" "method" "n" "x" "y" "yleft" "yright"
utils::ls.str(environment(Fn12))
stopifnot(all.equal(quantile(Fn12), quantile(y)))
###----------------- Plotting --------------------------
require(graphics)
op <- par(mfrow = c(3, 1), mgp = c(1.5, 0.8, 0), mar = .1+c(3,3,2,1))
F10 <- ecdf(rnorm(10))
summary(F10)
plot(F10)
plot(F10, verticals = TRUE, do.points = FALSE)
plot(Fn12 , lwd = 2) ; mtext("lwd = 2", adj = 1)
xx <- unique(sort(c(seq(-3, 2, length = 201), knots(Fn12))))
lines(xx, Fn12(xx), col = "blue")
abline(v = knots(Fn12), lty = 2, col = "gray70")
plot(xx, Fn12(xx), type = "o", cex = .1) #- plot.default {ugly}
plot(Fn12, col.hor = "red", add = TRUE) #- plot method
abline(v = knots(Fn12), lty = 2, col = "gray70")
## luxury plot
plot(Fn12, verticals = TRUE, col.points = "blue",
col.hor = "red", col.vert = "bisque")
##-- this works too (automatic call to ecdf(.)):
plot.ecdf(rnorm(24))
title("via simple plot.ecdf(x)", adj = 1)
par(op)
# }
```

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