This is a method for the dplyr select() generic. It is translated to the j argument of [.data.table.

# S3 method for dtplyr_step
select(.data, ...)

Arguments

.data

A lazy_dt().

...

<tidy-select> One or more unquoted expressions separated by commas. Variable names can be used as if they were positions in the data frame, so expressions like x:y can be used to select a range of variables.

Examples

library(dplyr, warn.conflicts = FALSE) dt <- lazy_dt(data.frame(x1 = 1, x2 = 2, y1 = 3, y2 = 4)) dt %>% select(starts_with("x"))
#> Source: local data table [1 x 2] #> Call: `_DT28`[, .(x1, x2)] #> #> x1 x2 #> <dbl> <dbl> #> 1 1 2 #> #> # Use as.data.table()/as.data.frame()/as_tibble() to access results
dt %>% select(ends_with("2"))
#> Source: local data table [1 x 2] #> Call: `_DT28`[, .(x2, y2)] #> #> x2 y2 #> <dbl> <dbl> #> 1 2 4 #> #> # Use as.data.table()/as.data.frame()/as_tibble() to access results
dt %>% select(z1 = x1, z2 = x2)
#> Source: local data table [1 x 2] #> Call: `_DT28`[, .(z1 = x1, z2 = x2)] #> #> z1 z2 #> <dbl> <dbl> #> 1 1 2 #> #> # Use as.data.table()/as.data.frame()/as_tibble() to access results