unique mean and error of a vector with repetitions

input: vec x with repetitions and F(x). return: mean and error of F(unique(x))

this function takes a vector x that contains repetitions and a function of x.
This means that for every value of x there are multiple values of F(x)
The function returens a vector y which is the values of x without the repetitions,
a vector V that is the bootsrtap mean of Fx - V_i = mean(F(xi)) where all
xi are the same, and a vector errBS with is the bootstrap error of the
mean.