tar_assign {tarchetypes} | R Documentation |
An assignment-based pipeline DSL
Description
An assignment-based domain-specific language for pipeline construction.
Usage
tar_assign(targets)
Arguments
targets |
An expression with special syntax to define a
collection of targets in a pipeline.
Example:
|
Value
A list of tar_target()
objects.
See the "Target objects" section for background.
Target objects
Most tarchetypes
functions are target factories,
which means they return target objects
or lists of target objects.
Target objects represent skippable steps of the analysis pipeline
as described at https://books.ropensci.org/targets/.
Please read the walkthrough at
https://books.ropensci.org/targets/walkthrough.html
to understand the role of target objects in analysis pipelines.
For developers, https://wlandau.github.io/targetopia/contributing.html#target-factories explains target factories (functions like this one which generate targets) and the design specification at https://books.ropensci.org/targets-design/ details the structure and composition of target objects.
Examples
if (identical(Sys.getenv("TAR_LONG_EXAMPLES"), "true")) {
targets::tar_dir({ # tar_dir() runs code from a temporary directory.
write.csv(airquality, "data.csv", row.names = FALSE)
targets::tar_script({
library(tarchetypes)
tar_option_set(packages = c("readr", "dplyr", "ggplot2"))
tar_assign({
file <- tar_target("data.csv", format = "file")
data <- read_csv(file, col_types = cols()) |>
filter(!is.na(Ozone)) |>
tar_target()
model = lm(Ozone ~ Temp, data) |>
coefficients() |>
tar_target()
plot <- {
ggplot(data) +
geom_point(aes(x = Temp, y = Ozone)) +
geom_abline(intercept = model[1], slope = model[2]) +
theme_gray(24)
} |>
tar_target()
})
})
targets::tar_make()
})
}