[.ggobiDataset {Rggobi}R Documentation

Subsetting extraction and assignments for ggobi datasets

Description

These functions/methods allow one to treat a ggobi dataset as if it were a local matrix/data.frame. One can extract and assign elements within the dataset. There is a fundamental difference between the two assignment operators ([<- and [[<-). The [<- operator first retrieves all the data from the GGobi dataset, does the replacement using R's semantics and then resets the data. [[<- attempts directly replaces the value(s) specified by the index d within the GGobi. This is much more efficient as it avoids copying all the data. However, the semantics are not the same as the usual R subsetting. This is currently intended for changing individual points and support for vector indices will probably change.

Usage

"[.ggobiDataset"(x, ..., drop = FALSE)
"[<-.ggobiDataset"(x, i, j, value)
"[[<-.ggobiDataset"(x, i, j, value)

Arguments

x the ggobiDataset object
drop the drop argument as in the regular matrix and data frame subsetting functions. This is passed to the relevant subset operation when the data is transferred.
... the indices by which to subset the dataset
i the indices for selecting the rows of the matrix to which the values are to be assigned.
j the indices for selecting the columns of the matrix to which the values are to be assigned.
value the values to assigned to the elements of the matrix.

Details

At present, the assignment is unecessarily expensive in that it transfers the entire dataset from ggobi, performs the usual subsetting operations and then transfers the results back into the variables of the original dataset. This can be made smarter.

Value

The subsetting operator [ returns the result of subsetting the matrix corresponding to the ggobi dataset. This is identical to the functionality of the subsetting of a matrix.
The assignment operator [<- returns the original ggobiDataset object. The side-effect is to modify the contents of the internal ggobi dataset.

Author(s)

Duncan Temple Lang

References

http://www.ggobi.org

See Also

setVariableValues.ggobi getVariable.ggobi getData.ggobi names.ggobiDataset dimnames.ggobiDataset

Examples

 g <- ggobi(system.file("data", "flea.xml", package="Rggobi"), args="-noinit")
 d <- g[[1]]
 d[1,1] <- 100
# d[[1,1]] <- 100

 g$getData()[1,1]

 d[1:3,1:2] <- .3
 d[1:3,1:2]

[Package Rggobi version 1.1-2 Index]