Apply a function over a list-like object preserving its attributes

This function apply a function over a list-like object preserving its attributes and simplify (if requested) the list as sapply function does. slapply returns a list of the same length as 'x', each element of which is the result of applying FUN to the corresponding element of 'x'.

Usage

slapply(
  x,
  FUN,
  keep.attr = FALSE,
  class = NULL,
  simplify = TRUE,
  USE.NAMES = TRUE,
  ...
)

Arguments

x: A list-like or vector-like object.
FUN, ...: The same as described in lapply.
keep.attr: Logic. If TRUE, then the original attributes from 'x' are preserved in the returned list. Default is FALSE.
class: Name of the class to which the returned list belongs to. Default is NULL.
simplify, USE.NAMES: The same as described in sapply.

Value

Same as in ?base::lapply if keep.attr = FALSE. Otherwise same values preserving original attributes from 'x'.

Author

Robersy Sanchez (https://genomaths.com).

Examples

## Create a list
x <- list(a = seq(10), beta = exp(seq(-3, 3)), 
          logic = c(TRUE, FALSE, FALSE, TRUE))
class(x) <- "nice"

## To compute the list mean for each list element using 'base::lapply'
class(slapply(x, mean, simplify = FALSE))
#> [1] "list"

## Simply 'base::lapply' preserving attributes
slapply(x, mean, keep.attr = TRUE, simplify = FALSE)
#> $a
#> [1] 5.5
#> 
#> $beta
#> [1] 4.535125
#> 
#> $logic
#> [1] 0.5
#> 
#> attr(,"class")
#> [1] "nice"

## To preserve attributes and simplify
slapply(x, mean, keep.attr = TRUE, simplify = TRUE)
#>        a     beta    logic 
#> 5.500000 4.535125 0.500000 
#> attr(,"class")
#> [1] "nice"