ggRandomForests (version 1.1.2)

surface_matrix: Construct a set of (x, y, z) matrices for surface plotting a gg_partial_coplot object

Description

Construct a set of (x, y, z) matrices for surface plotting a gg_partial_coplot object

Usage

surface_matrix(dta, xvar)

Arguments

dta

a gg_partial_coplot object containing at least 3 numeric columns of data

xvar

a vector of 3 column names from the data object, in (x, y, z) order

Details

To create a surface plot, the plot3D::surf3D function expects 3 matrices of n.x by n.y. Take the p+1 by n gg_partial_coplot object, and extract and construct the x, y and z matrices from the provided xvar column names.

Examples

## From vignette(randomForestRegression, package="ggRandomForests")
##
# Load the stored rfsrc and partial coplot data.
data(rfsrc_Boston)
data(partial_coplot_Boston_surf)

# Find the quantile points to create 50 interval groups
rm_pts <- quantile_cuts(rfsrc_Boston$xvar$rm, groups=50)

# Instead of groups, we want the raw rm point values,
# To make the dimensions match, we need to repeat the values
# for each of the 50 points in the lstat direction
rm.tmp <- do.call(c,lapply(rm_pts[-1],
                           function(grp){rep(grp, 50)}))

# attach the data to the gg_partial_coplot
partial_coplot_Boston_surf$rm <- rm.tmp

srf <- surface_matrix(partial_coplot_Boston_surf, c("lstat", "rm", "yhat"))

# surf3D is in the plot3D package.
library(plot3D)
surf3D(x=srf$x, y=srf$y, z=srf$z,
       colkey=FALSE, border = "black", bty="b2",
       xlab="Lower Status", ylab="Average Rooms", zlab="Median Value")