Select distinct/unique rows in data.table

Source: R/distinct.R

Analogous function for distinct in dplyr

distinct(.data, ..., .keep_all = FALSE)

Arguments

.data

data.table

...

Optional variables to use when determining uniqueness. If there are multiple rows for a given combination of inputs, only the first row will be preserved. If omitted, will use all variables.

.keep_all

If TRUE, keep all variables in data.table. If a combination of ... is not distinct, this keeps the first row of values.

Value

data.table

See also

distinct

Examples


 a = as.data.table(iris)
 b = as.data.table(mtcars)
 a %>% distinct(Species)
#>       Species
#>        <fctr>
#> 1:     setosa
#> 2: versicolor
#> 3:  virginica
 b %>% distinct(cyl,vs,.keep_all = TRUE)
#>      mpg   cyl  disp    hp  drat    wt  qsec    vs    am  gear  carb
#>    <num> <num> <num> <num> <num> <num> <num> <num> <num> <num> <num>
#> 1:  21.0     6 160.0   110  3.90 2.620 16.46     0     1     4     4
#> 2:  22.8     4 108.0    93  3.85 2.320 18.61     1     1     4     1
#> 3:  21.4     6 258.0   110  3.08 3.215 19.44     1     0     3     1
#> 4:  18.7     8 360.0   175  3.15 3.440 17.02     0     0     3     2
#> 5:  26.0     4 120.3    91  4.43 2.140 16.70     0     1     5     2