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Modify a user-defined function written in R

I have the following code written in R:

Gems <- data.frame(
  Color = c("Red", "Blue", "Purple", "Orange", 
            "Green", "Pink", "White", "Black", "Yellow"),
  Weight = round(runif(9,0.5,5),2),
  Value = round(abs(rnorm(9,0,5))+0.5,2)
)

InitilzePop <- function(size){
  pop <- (t(sapply(1:size, function(pop) round(runif(nrow(Gems),0, 1), 0))))
  colnames(pop)<- Gems$Color
  return(pop)
}

I want to change this part of the code round(runif(nrow(Gems),0, 1), 0) in a way that instead of generating outputs from random values, it takes values based on the size of Gems from a vector, for instance,

vector <- c(1,1,0,0,0,1,0,1,0,0,1,1,1,0,0,0,0,1,1,1,
            1,1,0,0,1,1,1,0,0,1,1,1,0,0,1,1,1,0)

I was wondering if it is possible to solve it without using base::sample(). Please consider the following:

myvector <- c(1,1,0,0,0,1,0,1,0,0,1,1,1,0,0,0,0,1,1,1,1,1,0,0,1,1,1,0,0,1,1,1,0,0,1,1,1,0)

when calling InitilzePop(2) the output will be:

#>      Red Blue Purple Orange Green Pink White Black Yellow
#> [1,]   1    1      0      0     0    1     0     1      0
#> [2,]   0    1      1      1     0    0     0     0      1

And the vector will be: myvector <- c(1,1,1,1,0,0,1,1,1,0,0,1,1,1,0,0,1,1,1,0)

Hence, next time when calling InitilzePop(2) the output will be:

#>      Red Blue Purple Orange Green Pink White Black Yellow
#> [1,]   1    1      1      1    0    0     1     1      1
#> [2,]   0    0      1      1    1    0     0     1      1

And the vector will be: myvector <- c(1,0)

Solution

  • This will get you the described behavior. The global assignment, <<-, will modify myvector at each InitilzePop call. The desired matrices are more easily (and efficiently) built using the matrix function.

    Gems <- data.frame(
  Color = c("Red", "Blue", "Purple", "Orange", 
            "Green", "Pink", "White", "Black", "Yellow"),
  Weight = round(runif(9,0.5,5),2),
  Value = round(abs(rnorm(9,0,5))+0.5,2)
)

InitilzePop <- function(size) {
  n <- size*nrow(Gems)
  vec <- myvector[1:n]
  myvector <<- myvector[-1:-n]
  matrix(vec, size, nrow(Gems), TRUE, list(NULL, Gems$Color))
}

myvector <- c(1,1,0,0,0,1,0,1,0,0,1,1,1,0,0,0,0,1,1,1,1,1,0,0,1,1,1,0,0,1,1,1,0,0,1,1,1,0)
InitilzePop(2)
#>      Red Blue Purple Orange Green Pink White Black Yellow
#> [1,]   1    1      0      0     0    1     0     1      0
#> [2,]   0    1      1      1     0    0     0     0      1
myvector
#>  [1] 1 1 1 1 0 0 1 1 1 0 0 1 1 1 0 0 1 1 1 0
InitilzePop(2)
#>      Red Blue Purple Orange Green Pink White Black Yellow
#> [1,]   1    1      1      1     0    0     1     1      1
#> [2,]   0    0      1      1     1    0     0     1      1
myvector
#> [1] 1 0