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rpurrr

Mapping a function in R with multiple arguments

I am looking for the R way (preferably "Tidyverse way") to map a function to multiple arguments.

I have created a function with multiple arguments:

product <- function(a = 1, b = 2, c = 3, d = 4){
  return(c(a, b, c, d, a*b*c*d))
}

I am looking for the most convenient way to use the function multiple times with different parameters. I am able to use the map functions from the purrr package (to some extent), but there are two scenarios in which I am stuck:

1) If I only want to alter c

2) If I want to alter for example c and d*

My solution is rather cumbersome. I either create a wrapper around the function for my specific needs (so a lot of wrappers...) or use the pmap function from the purrr package, e.g.:

a <- list(1, 1, 1, 1, 1)
b <- list(2, 2, 2, 2, 2)
c <- list(1, 2, 3, 4, 5)
d <- list(4, 4, 4, 4, 4)
    
pmap(list(a, b, c, d), product)

Is there a better way to solve this?

Solution

  • Does this help?

    If you only want to change c

    map(1:4, product, a = 1, b = 2, d = 4)

    If you only want to change c and d

    pmap(list(1:4, 11:14), product, a = 1, b = 2)

    And a suggestion: don't use c as an object name. c is the function that creates a vector. Something else is better coding style.