R Under development (unstable) (2025-01-06 r87534 ucrt) -- "Unsuffered Consequences"
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> require("fitdistrplus")
Loading required package: fitdistrplus
Loading required package: MASS
Loading required package: survival
> nsample <- 1e6
> nsample <- 10
> 
> #### (1) Gamma example ####
> 
> truetheta <- c("alpha"=3, "beta"=1/2)
> x <- rgamma(nsample, truetheta["alpha"], truetheta["beta"])
> f1 <- mmedist(x, "gamma", order=1:2, calcvcov = TRUE)
> f1$vcov
          shape       rate
shape 2.8635913 0.45492283
rate  0.4549228 0.08064197
> if(FALSE)
+ {
+   memp  <-  function(x, order) mean(x^order)
+   require("actuar")
+   fitdistrplus:::mme.vcov(as.numeric(truetheta), fix.arg=NULL, order=1:2, obs=x, mdistnam=mgamma, memp, weights=NULL)
+ }
> 
> if(FALSE)
+ {
+   mmedist(rgamma(1e2, truetheta["alpha"], truetheta["beta"]), "gamma", order=1:2, calcvcov = TRUE)$vcov
+   mmedist(rgamma(1e3, truetheta["alpha"], truetheta["beta"]), "gamma", order=1:2, calcvcov = TRUE)$vcov
+   mmedist(rgamma(1e4, truetheta["alpha"], truetheta["beta"]), "gamma", order=1:2, calcvcov = TRUE)$vcov
+ }
> 
> 
> # (2) fit a Pareto distribution
> #
> 
> if(any(installed.packages()[, "Package"] == "actuar"))
+ {
+   require("actuar")
+   #simulate a sample
+   x4 <- rpareto(nsample, 6, 2)
+   
+   #empirical raw moment
+   memp <- function(x, order)
+     mean(x^order)
+   
+   #fit
+   res <- mmedist(x4, "pareto", order=c(1, 2), memp=memp, start=c(shape=10, scale=10), 
+           lower=1, upper=Inf, calcvcov = TRUE)
+ }
Loading required package: actuar

Attaching package: 'actuar'

The following objects are masked from 'package:stats':

    sd, var

The following object is masked from 'package:grDevices':

    cm

> 
> proc.time()
   user  system elapsed 
   1.40    0.29    1.68