R Under development (unstable) (2021-10-13 r81047) -- "Unsuffered Consequences"
Copyright (C) 2021 The R Foundation for Statistical Computing
Platform: x86_64-pc-linux-gnu (64-bit)

R is free software and comes with ABSOLUTELY NO WARRANTY.
You are welcome to redistribute it under certain conditions.
Type 'license()' or 'licence()' for distribution details.

R is a collaborative project with many contributors.
Type 'contributors()' for more information and
'citation()' on how to cite R or R packages in publications.

Type 'demo()' for some demos, 'help()' for on-line help, or
'help.start()' for an HTML browser interface to help.
Type 'q()' to quit R.

> library(parallel)
> 
> if(require(boot, quietly = TRUE)) {
+     cd4.rg <- function(data, mle) MASS::mvrnorm(nrow(data), mle$m, mle$v)
+     cd4.mle <- list(m = colMeans(cd4), v = var(cd4))
+     mc <- getOption("mc.cores", 2)
+     run1 <- function(...) boot(cd4, corr, R = 500, sim = "parametric",
+                                ran.gen = cd4.rg, mle = cd4.mle)
+     ## To make this reproducible:
+     set.seed(123, "L'Ecuyer"); mc.reset.stream()
+     res <- mclapply(seq_len(mc), run1)
+     cd4.boot <- do.call(c, res)
+     boot.ci(cd4.boot,  type = c("norm", "basic", "perc"),
+             conf = 0.9, h = atanh, hinv = tanh)
+ }
BOOTSTRAP CONFIDENCE INTERVAL CALCULATIONS
Based on 1000 bootstrap replicates

CALL : 
boot.ci(boot.out = cd4.boot, conf = 0.9, type = c("norm", "basic", 
    "perc"), h = atanh, hinv = tanh)

Intervals : 
Level      Normal              Basic              Percentile     
90%   ( 0.4575,  0.8547 )   ( 0.4703,  0.8575 )   ( 0.4964,  0.8663 )  
Calculations on Transformed Scale;  Intervals on Original Scale
> 
> proc.time()
   user  system elapsed 
  0.388   0.124   0.352