slice {xgboost}

Get a new DMatrix containing the specified rows of original xgb.DMatrix object

Description

Get a new DMatrix containing the specified rows of original xgb.DMatrix object

Usage

slice(object, ...)

## S3 method for class 'xgb.DMatrix'
slice(object, idxset, ...)

## S3 method for class 'xgb.DMatrix'
object[idxset, colset = NULL]

Arguments

object

Object of class "xgb.DMatrix"

...

other parameters (currently not used)

idxset

a integer vector of indices of rows needed

colset

currently not used (columns subsetting is not available)

Examples

data(agaricus.train, package='xgboost')
dtrain <- with(agaricus.train, xgb.DMatrix(data, label = label, nthread = 2))

dsub <- slice(dtrain, 1:42)
labels1 <- getinfo(dsub, 'label')
dsub <- dtrain[1:42, ]
labels2 <- getinfo(dsub, 'label')
all.equal(labels1, labels2)