Modify records in a data.table

Source: R/modify.R

Modify records in a data.table using modification rules specified in a modifier object.

# S4 method for data.table,modifier
modify(dat, x, copy = NULL, sequential = TRUE, ...)

Arguments

dat

data.table() object
x

dcmodify::modifier object.
copy

if TRUE modify copy of table.
sequential

if TRUE (default), steps will be executed in sequence, so order matters.
...

unused

Details

This is a more efficient implementation then coercing the data.table to a data.frame and use that implementation.

See also

Other modify: setmodify()

Examples

library(data.table)

m <- modifier( if (age > 130) age = 130
             , income[age < 12] <- 0
             )

dat <- fread(text =
"age, income
 140,  300
  11, 2000
  25, 3000"
)

# modify a copy of the data
dat_m <- modify(dat, m, copy = TRUE)
print(dat_m)

#>    age income
#> 1: 130    300
#> 2:  11      0
#> 3:  25   3000

# the data it self
setmodify(dat, m)
print(dat)

#>    age income
#> 1: 130    300
#> 2:  11      0
#> 3:  25   3000