by-lapply.Rd
This function is a wrapper for calling lapply on the list resulting from first calling splitBy.
lapply_by(data, formula, FUN, ...)
lapplyBy(formula, data = parent.frame(), FUN, ...)
sapply_by(data, formula, FUN, ..., simplify = TRUE, USE.NAMES = TRUE)
sapplyBy(
formula,
data = parent.frame(),
FUN,
...,
simplify = TRUE,
USE.NAMES = TRUE
)
A dataframe.
A formula describing how data should be split.
A function to be applied to each element in the split list, see 'Examples' below.
optional arguments to FUN.
Same as for sapply
Same as for sapply
A list.
fun <- function(x) range(x$uptake)
lapplyBy(~Treatment + Type, data=CO2, FUN=fun)
#> $`nonchilled|Quebec`
#> [1] 13.6 45.5
#>
#> $`chilled|Quebec`
#> [1] 9.3 42.4
#>
#> $`nonchilled|Mississippi`
#> [1] 10.6 35.5
#>
#> $`chilled|Mississippi`
#> [1] 7.7 22.2
#>
sapplyBy(~Treatment + Type, data=CO2, FUN=fun)
#> nonchilled|Quebec chilled|Quebec nonchilled|Mississippi
#> [1,] 13.6 9.3 10.6
#> [2,] 45.5 42.4 35.5
#> chilled|Mississippi
#> [1,] 7.7
#> [2,] 22.2
# Same as
lapply(splitBy(~Treatment + Type, data=CO2), FUN=fun)
#> $`nonchilled|Quebec`
#> [1] 13.6 45.5
#>
#> $`chilled|Quebec`
#> [1] 9.3 42.4
#>
#> $`nonchilled|Mississippi`
#> [1] 10.6 35.5
#>
#> $`chilled|Mississippi`
#> [1] 7.7 22.2
#>