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Figure 3.40
Snapshots of a three-dimensional PCA biplot of the copper froth data.
The quality of the three-dimensional PCA biplot is 94.23%. The top right snapshot
shows a zoomed view of the biplot in the top left panel. The snapshots in the bottom
panels are also zoomed views of the top left biplot but have been rotated as well. The
three-dimensional biplots clearly show some group structure in the data.
biplot is drawn in an
rgl
window. The plot can then be interactively rotated and zoomed
using the mouse buttons. Figure 3.40 contains snapshots of the results of the call.
PCAbipl(CopperFroth.data[,1:8], scaled.mat = TRUE,
dim.biplot = 3, colours = "green", predictions.3D = TRUE,
size.points.3d = 0.25)
Note that by default the three-dimensional biplot contains a grey coloured plane through
the origin separating points above the plane from those below the plane. We suggest
that readers try the above call and then interactively explore the three-dimensional PCA
