Function

Datos

set.seed(123)
x <- sort(rnorm(100,3,0.3))
y <- sort(runif(100,1.01,1.15),decreasing = T)

Function

fun <- function(x,y){
  vectorr = NULL
  for (i in 1:(length(x)/5)){
    n <- ((cov(x[1:(5*i)],y[1:(5*i)])/(sqrt(var(x[1:(5*i)])*var(y[1:(5*i)])))))
    vectorr = c(vectorr,n) 
  }
  return(vectorr)
}
fun(x,y)

##  [1] -0.9777246 -0.8022527 -0.8118489 -0.8686414 -0.8848385 -0.8982684
##  [7] -0.9105781 -0.9142804 -0.9116737 -0.9206417 -0.9288982 -0.9388496
## [13] -0.9481794 -0.9536258 -0.9599993 -0.9663662 -0.9714357 -0.9757927
## [19] -0.9778213 -0.9715714

precio = rnorm(50,2500,300)
meanF <- function(k){
  vectorr = NULL
  for (i in 0:(length(k)-1)){
    n <- mean(precio[1:(length(k)-i)])
    vectorr = c(vectorr,n)
  }
  return(vectorr)
}  
meanF(precio)

##  [1] 2511.642 2519.138 2523.356 2531.840 2528.614 2515.936 2525.235 2532.069
##  [9] 2532.157 2535.317 2534.591 2539.319 2534.401 2534.643 2526.356 2528.799
## [17] 2531.731 2540.561 2545.106 2534.337 2546.115 2552.447 2549.643 2548.032
## [25] 2549.443 2564.573 2576.530 2552.095 2554.928 2556.610 2562.672 2560.144
## [33] 2554.871 2566.636 2558.865 2556.825 2569.817 2500.394 2531.931 2563.448
## [41] 2538.211 2554.943 2525.174 2544.732 2524.038 2545.669 2566.046 2688.898
## [49] 2733.517 2736.322

mean(precio[1:50])

## [1] 2511.642

mean(precio[1:49])

## [1] 2519.138

mean(precio[1:48])

## [1] 2523.356

repito <- function(k,rep){
  vectorr = NULL
  for (i in 1:rep){
    r <- sample(1:length(k),5)
    n <- mean(k[r])
    vectorr = c(vectorr,n)
  }
  return(vectorr)
}    
repito(precio,2)

## [1] 2657.792 2384.358