绘制理论CDF

Question

I am trying to plot the empirical cumulative distribution function and theoretical cumulative distribution function. This is my R code:

x=rgamma(40, 2, 1/3)
plot(ecdf(x))
lines(x, pgamma(x, shape = 2, scale = 3), type="l", col = "red")

But I got the graph in the attached file which I think it is not reasonable. What I do wrong?

Answer 1

Expanding on my comment... is this what you are looking for?

x=rgamma(40, 2, 1/3)
plot(ecdf(x))
curve(pgamma(x, shape = 2, scale = 3), 
      0, 30, 
      add=TRUE,
      col="red")

This results in the following plot: