I am writing a code for estimating the parameter of a GPD using weighted nonlinear least square(WNLS) method. The WNLS method consist of 2 steps
step 1: $(\hat{\xi_1} , \hat{b_1}) = arg\ \min_{(\xi,b)} \sum_{i=1}^{n} [\log(1-F_n(x_i)) - log(1-G_{\xi,b}(x_i))]$, here $F_n$ is the ECDF and $1-G_{\xi,b}$ is the generalized pareto distribution.
Can anyone let me know how to calculate EDF function $F_n$ for a data "X" in R?
Does ecdf(X)(X) will calculate the ECDF? If so then, what is the need for ecdf(X) other than plotting? Also it would be really helpful if someone share some example code which involves the calculation of ECDF for data.