tar_stars {geotargets} | R Documentation |
Create a stars stars Target
Description
Provides a target format for stars
objects. Note that most or all stars
objects work with ordinary tar_target()
and do not necessarily need
geotargets
target factories the way terra
objects do. Currently
tar_stars()
has the same limitations as stars::write_stars()
, so use with
caution.
Usage
tar_stars(
name,
command,
pattern = NULL,
proxy = FALSE,
mdim = FALSE,
ncdf = FALSE,
driver = geotargets_option_get("gdal.raster.driver"),
options = geotargets_option_get("gdal.raster.creation.options"),
type = geotargets_option_get("gdal.raster.data.type"),
...,
tidy_eval = targets::tar_option_get("tidy_eval"),
packages = targets::tar_option_get("packages"),
library = targets::tar_option_get("library"),
repository = targets::tar_option_get("repository"),
error = targets::tar_option_get("error"),
memory = targets::tar_option_get("memory"),
garbage_collection = targets::tar_option_get("garbage_collection"),
deployment = targets::tar_option_get("deployment"),
priority = targets::tar_option_get("priority"),
resources = targets::tar_option_get("resources"),
storage = targets::tar_option_get("storage"),
retrieval = targets::tar_option_get("retrieval"),
cue = targets::tar_option_get("cue"),
description = targets::tar_option_get("description")
)
tar_stars_proxy(
name,
command,
pattern = NULL,
mdim = FALSE,
ncdf = FALSE,
driver = geotargets_option_get("gdal.raster.driver"),
options = geotargets_option_get("gdal.raster.creation.options"),
type = geotargets_option_get("gdal.raster.data.type"),
...,
tidy_eval = targets::tar_option_get("tidy_eval"),
packages = targets::tar_option_get("packages"),
library = targets::tar_option_get("library"),
repository = targets::tar_option_get("repository"),
error = targets::tar_option_get("error"),
memory = targets::tar_option_get("memory"),
garbage_collection = targets::tar_option_get("garbage_collection"),
deployment = targets::tar_option_get("deployment"),
priority = targets::tar_option_get("priority"),
resources = targets::tar_option_get("resources"),
storage = targets::tar_option_get("storage"),
retrieval = targets::tar_option_get("retrieval"),
cue = targets::tar_option_get("cue"),
description = targets::tar_option_get("description")
)
Arguments
name |
Symbol, name of the target. A target name must be a valid name
for a symbol in R, and it must not start with a dot. See
targets::tar_target() for more information.
|
command |
R code to run the target.
|
pattern |
Code to define a dynamic branching pattern for a target. See
targets::tar_target() for more information.
|
proxy |
logical. Passed to stars::read_stars() . If TRUE the target
will be read as an object of class stars_proxy . Otherwise, the object is
class stars .
|
mdim |
logical. Use the Multidimensional Raster Data Model via
stars::write_mdim() ? Default: FALSE . Only supported for some drivers,
e.g. "netCDF" or "Zarr" .
|
ncdf |
logical. Use the NetCDF library directly to read data via
stars::read_ncdf() ? Default: FALSE . Only supported for
driver="netCDF" .
|
driver |
character. File format expressed as GDAL driver names passed to
stars::write_stars() . See sf::st_drivers() .
|
options |
character. GDAL driver specific datasource creation options
passed to stars::write_stars() .
|
type |
character. character. Data type passed to stars::write_stars() .
One of: "Byte" , "UInt16" , "UInt32" , "UInt64" , "Int16" , "Int32" ,
"Int64" , "Float32" , "Float64" .
|
... |
Additional arguments not yet used.
|
tidy_eval |
Logical, whether to enable tidy evaluation
when interpreting command and pattern . If TRUE , you can use the
"bang-bang" operator !! to programmatically insert
the values of global objects.
|
packages |
Character vector of packages to load right before
the target runs or the output data is reloaded for
downstream targets. Use tar_option_set() to set packages
globally for all subsequent targets you define.
|
library |
Character vector of library paths to try
when loading packages .
|
repository |
Character of length 1, remote repository for target
storage. Choices:
Note: if repository is not "local" and format is "file"
then the target should create a single output file.
That output file is uploaded to the cloud and tracked for changes
where it exists in the cloud. The local file is deleted after
the target runs.
|
error |
Character of length 1, what to do if the target
stops and throws an error. Options:
-
"stop" : the whole pipeline stops and throws an error.
-
"continue" : the whole pipeline keeps going.
-
"null" : The errored target continues and returns NULL .
The data hash is deliberately wrong so the target is not
up to date for the next run of the pipeline. In addition,
as of targets version 1.8.0.9011, a value of NULL is given
to upstream dependencies with error = "null" if loading fails.
-
"abridge" : any currently running targets keep running,
but no new targets launch after that.
-
"trim" : all currently running targets stay running. A queued
target is allowed to start if:
It is not downstream of the error, and
It is not a sibling branch from the same tar_target() call
(if the error happened in a dynamic branch).
The idea is to avoid starting any new work that the immediate error
impacts. error = "trim" is just like error = "abridge" ,
but it allows potentially healthy regions of the dependency graph
to begin running.
(Visit https://books.ropensci.org/targets/debugging.html
to learn how to debug targets using saved workspaces.)
|
memory |
Character of length 1, memory strategy. Possible values:
-
"auto" (default): equivalent to memory = "transient" in almost
all cases. But to avoid superfluous reads from disk,
memory = "auto" is equivalent to memory = "persistent" for
for non-dynamically-branched targets that other targets
dynamically branch over. For example: if your pipeline has
tar_target(name = y, command = x, pattern = map(x)) ,
then tar_target(name = x, command = f(), memory = "auto")
will use persistent memory in order to avoid rereading all of x
for every branch of y .
-
"transient" : the target gets unloaded
after every new target completes.
Either way, the target gets automatically loaded into memory
whenever another target needs the value.
-
"persistent" : the target stays in memory
until the end of the pipeline (unless storage is "worker" ,
in which case targets unloads the value from memory
right after storing it in order to avoid sending
copious data over a network).
For cloud-based file targets
(e.g. format = "file" with repository = "aws" ),
the memory option applies to the
temporary local copy of the file:
"persistent" means it remains until the end of the pipeline
and is then deleted,
and "transient" means it gets deleted as soon as possible.
The former conserves bandwidth,
and the latter conserves local storage.
|
garbage_collection |
Logical: TRUE to run base::gc()
just before the target runs, in whatever R process it is about to run
(which could be a parallel worker).
FALSE to omit garbage collection.
Numeric values get converted to FALSE .
The garbage_collection option in tar_option_set()
is independent of the
argument of the same name in tar_target() .
|
deployment |
Character of length 1. If deployment is
"main" , then the target will run on the central controlling R process.
Otherwise, if deployment is "worker" and you set up the pipeline
with distributed/parallel computing, then
the target runs on a parallel worker. For more on distributed/parallel
computing in targets , please visit
https://books.ropensci.org/targets/crew.html.
|
priority |
Deprecated on 2025-04-08 (targets version 1.10.1.9013).
targets has moved to a more efficient scheduling algorithm
(https://github.com/ropensci/targets/issues/1458)
which cannot support priorities.
The priority argument of tar_target() no longer has a reliable
effect on execution order.
|
resources |
Object returned by tar_resources()
with optional settings for high-performance computing
functionality, alternative data storage formats,
and other optional capabilities of targets .
See tar_resources() for details.
|
storage |
Character string to control when the output of the target
is saved to storage. Only relevant when using targets
with parallel workers (https://books.ropensci.org/targets/crew.html).
Must be one of the following values:
-
"worker" (default): the worker saves/uploads the value.
-
"main" : the target's return value is sent back to the
host machine and saved/uploaded locally.
-
"none" : targets makes no attempt to save the result
of the target to storage in the location where targets
expects it to be. Saving to storage is the responsibility
of the user. Use with caution.
|
retrieval |
Character string to control when the current target
loads its dependencies into memory before running.
(Here, a "dependency" is another target upstream that the current one
depends on.) Only relevant when using targets
with parallel workers (https://books.ropensci.org/targets/crew.html).
Must be one of the following values:
-
"auto" (default): equivalent to retrieval = "worker" in almost all
cases. But to avoid unnecessary reads from disk, retrieval = "auto"
is equivalent to retrieval = "main" for dynamic branches that
branch over non-dynamic targets. For example: if your pipeline has
tar_target(x, command = f()) , then
tar_target(y, command = x, pattern = map(x), retrieval = "auto")
will use "main" retrieval in order to avoid rereading all of x
for every branch of y .
-
"worker" : the worker loads the target's dependencies.
-
"main" : the target's dependencies are loaded on the host machine
and sent to the worker before the target runs.
-
"none" : targets makes no attempt to load its
dependencies. With retrieval = "none" , loading dependencies
is the responsibility of the user. Use with caution.
|
cue |
An optional object from tar_cue() to customize the
rules that decide whether the target is up to date.
|
description |
Character of length 1, a custom free-form human-readable
text description of the target. Descriptions appear as target labels
in functions like tar_manifest() and tar_visnetwork() ,
and they let you select subsets of targets for the names argument of
functions like tar_make() . For example,
tar_manifest(names = tar_described_as(starts_with("survival model")))
lists all the targets whose descriptions start with the character
string "survival model" .
|
Value
target class "tar_stem" for use in a target pipeline
Note
The iteration
argument is unavailable because it is hard-coded to
"list"
, the only option that works currently.
See Also
targets::tar_target()
Examples
# For CRAN. Ensures these examples run under certain conditions.
# To run this locally, run the code inside this if statement
if (Sys.getenv("TAR_LONG_EXAMPLES") == "true") {
targets::tar_dir({ # tar_dir() runs code from a temporary directory.
library(geotargets)
targets::tar_script({
list(
geotargets::tar_stars(
stars_example,
stars::read_stars(
system.file("tif", "olinda_dem_utm25s.tif", package = "stars")
),
type = "Int64"
)
)
})
targets::tar_make()
x <- targets::tar_read(stars_example)
})
}
[Package
geotargets version 0.3.0
Index]