rxDForestUtils: Utility Functions for rxDForest

發行項
07/15/2019

Description

Utility Functions for rxDForest.

Usage

  rxVarImpPlot(x, sort = TRUE, n.var = 30, main = deparse(substitute(x)),   ...  )
  rxLeafSize(x, use.weight = TRUE)
  rxTreeDepth(x)
  rxTreeSize(x, terminal = TRUE)
  rxVarUsed(x, by.tree = FALSE, count = TRUE)
  rxGetTree(x, k = 1)

Arguments

`x`

an object of class rxDForest or rxDTree.

`sort`

logical value. If TRUE, the variables will be sorted in decreasing importance.

`n.var`

an integer specifying the number of variables to show when sort=FALSE.

`main`

a character string specifying the main title for the plot.

`...`

other arguments to be passed on to dotchart.

`use.weight`

logical value. If TRUE, the leaf size is measured by the total weight of its observations instead of the total number of its observations.

`terminal`

logical value. If TRUE, only the terminal nodes will be counted.

`by.tree`

logical value. If TRUE, the list of variables used will be broken down by trees.

`count`

logical value. If TRUE, the frequencies that variables appear in trees will be returned.

`k`

an integer specifying the index of the tree to be extracted.

Value

rxVarImpPlot - plots a dotchart of the variable importance as measured by the decision forest.
rxLeafSize - returns the size of the terminal nodes in the decision forest.
rxTreeDepth - returns the depth of trees in the decision forest.
rxTreeSize - returns the size of trees in terms of the number of nodes in the decision forest.
rxVarUsed - finds out the variables actually used in the decision forest.
rxGetTree - extracts a single tree from the decision forest.

Author(s)

Microsoft Corporation Microsoft Technical Support

References

randomForest .

Examples


 set.seed(1234)

 # classification
 iris.sub <- c(sample(1:50, 25), sample(51:100, 25), sample(101:150, 25))
 iris.dforest <- rxDForest(Species ~ Sepal.Length + Sepal.Width + Petal.Length + Petal.Width, 
     data = iris[iris.sub, ], importance = TRUE)

 rxVarImpPlot(iris.dforest)
 rxTreeSize(iris.dforest)
 rxVarUsed(iris.dforest)
 rxGetTree(iris.dforest)

共用方式為