collect()returns a tibble, grouped if needed.compute()generates an intermediate assignment in the translation.as.data.table()returns a data.table.as.data.frame()returns a data frame.as_tibble()returns a tibble.
Usage
# S3 method for dtplyr_step
collect(x, ...)
# S3 method for dtplyr_step
compute(x, name = unique_name(), ...)
# S3 method for dtplyr_step
as.data.table(x, keep.rownames = FALSE, ...)
# S3 method for dtplyr_step
as.data.frame(x, ...)
# S3 method for dtplyr_step
as_tibble(x, ..., .name_repair = "check_unique")Arguments
- x
A lazy_dt
- ...
Arguments used by other methods.
- name
Name of intermediate data.table.
- keep.rownames
Ignored as dplyr never preserves rownames.
- .name_repair
Treatment of problematic column names
Examples
library(dplyr, warn.conflicts = FALSE)
dt <- lazy_dt(mtcars)
# Generate translation
avg_mpg <- dt %>%
filter(am == 1) %>%
group_by(cyl) %>%
summarise(mpg = mean(mpg))
# Show translation and temporarily compute result
avg_mpg
#> Source: local data table [3 x 2]
#> Call: `_DT3`[am == 1][, .(mpg = mean(mpg)), keyby = .(cyl)]
#>
#> cyl mpg
#> <dbl> <dbl>
#> 1 4 28.1
#> 2 6 20.6
#> 3 8 15.4
#>
#> # Use as.data.table()/as.data.frame()/as_tibble() to access results
# compute and return tibble
avg_mpg_tb <- as_tibble(avg_mpg)
avg_mpg_tb
#> # A tibble: 3 × 2
#> cyl mpg
#> <dbl> <dbl>
#> 1 4 28.1
#> 2 6 20.6
#> 3 8 15.4
# compute and return data.table
avg_mpg_dt <- data.table::as.data.table(avg_mpg)
avg_mpg_dt
#> cyl mpg
#> 1: 4 28.07500
#> 2: 6 20.56667
#> 3: 8 15.40000
# modify translation to use intermediate assignment
compute(avg_mpg)
#> Source: local data table [3 x 2]
#> Call:
#> _DT4 <- `_DT3`[am == 1][, .(mpg = mean(mpg)), keyby = .(cyl)]
#> `_DT4`
#>
#> cyl mpg
#> <dbl> <dbl>
#> 1 4 28.1
#> 2 6 20.6
#> 3 8 15.4
#>
#> # Use as.data.table()/as.data.frame()/as_tibble() to access results