TaskClassifST
SpatioTemporal Classification Task
This task specializes Task and TaskSupervised for
spatiotemporal classification problems. The target column is assumed to be a
factor. The task_type is set to "classif" and "spatiotemporal".
A spatial example task is available via tsk("ecuador"), a spatiotemporal
one via tsk("cookfarm").
The coordinate reference system passed during initialization must match the
one which was used during data creation, otherwise offsets of multiple meters
may occur. By default, coordinates are not used as features. This can be
changed by setting extra_args$coords_as_features = TRUE.
Super classes
mlr3::Task -> mlr3::TaskSupervised -> mlr3::TaskClassif -> TaskClassifST
Public fields
extra_args(named
list()) Additional task arguments set during construction. Required forconvert_task().
Methods
Public methods
Method new()
Create a new spatiotemporal resampling Task
Usage
TaskClassifST$new( id, backend, target, positive = NULL, extra_args = list(coords_as_features = FALSE, crs = NA, coordinate_names = NA) )
Arguments
id[character(1)]Identifier for the task.
backendDataBackend
Either a DataBackend, or any object which is convertible to a
DataBackend with as_data_backend(). E.g., a data.frame() will be
converted to a DataBackendDataTable.
target[character(1)]
Name of the target column.
positive[character(1)]
Only for binary classification: Name of the positive class.
The levels of the target columns are reordered accordingly, so that the
first element of $class_names is the positive class, and the second
element is the negative class.
extra_args[named list]
Additional task arguments set during construction. Required for
convert_task().
crs
[character(1)]Coordinate reference system. Either a PROJ string or an EPSG code.coords_as_features
[logical(1)]Whether the coordinates should also be used as features.coordinate_names
[character(2)]The variables names of the coordinates in the data.
Method coordinates()
Return the coordinates of the task
Usage
TaskClassifST$coordinates(rows = NULL)
Arguments
rowsRow IDs. Can be used to subset the returned coordinates.
Method print()
Print the task.
Usage
TaskClassifST$print(...)
Arguments
...Arguments passed to the
$print()method of the superclass.
Method clone()
The objects of this class are cloneable with this method.
Usage
TaskClassifST$clone(deep = FALSE)
Arguments
deepWhether to make a deep clone.
See Also
Other Task:
TaskRegrST,
mlr_tasks_cookfarm,
mlr_tasks_diplodia,
mlr_tasks_ecuador
Examples
# NOT RUN {
data = mlr3::as_data_backend(ecuador)
task = TaskClassifST$new("ecuador",
backend = data, target = "slides",
positive = "TRUE", extra_args = list(coordinate_names = c("x", "y"))
)
task$task_type
task$formula()
task$class_names
task$positive
task$negative
task$coordinates()
task$coordinate_names
# }