This package will order panels in scatterplot matrices and parallel
coordinate displays by some merit index. The package contains various
indices of merit, ordering functions, and enhanced versions of pairs and
parcoord which color panels according to their merit level. For details
on the methods used, consult “Clustering Visualisations of
Multidimensional Data”, Journal of Computational and Graphical
Statistics, vol. 13, (4), pp 788-806, 2004.
Displaying a correlation matrix
library(gclus)
#> Loading required package: cluster
data(longley)
longley.cor <- cor(longley)
longley.color <- dmat.color(longley.cor)
dmat.color assigns three colours to the correlations
according to the correlation magnitude. High correlations are in pink,
the middle third are in blue, and the botom third are in yellow.
par(mar=c(1,1,1,1))
plotcolors(longley.color,dlabels=rownames(longley.color))
If you want to change the colour scheme:
longley.color <- dmat.color(longley.cor, byrank=FALSE)
longley.color <- dmat.color(longley.cor, breaks=c(-1,0,.5,.8,1),
cm.colors(4))
The plot is easier to interpret if variables are reorded prior to
plotting.
par(mar=c(1,1,1,1))
longley.o <- order.hclust(longley.cor)
longley.color1 <- longley.color[longley.o,longley.o]
plotcolors(longley.color1,dlabels=rownames(longley.color1))
Displaying a pairs plot with coloured panels
cpairs is a version of pairs All the
high-correlation panels appear together in a block.
par(mar=c(1,1,1,1))
cpairs(longley, order= longley.o,panel.color= longley.color)
If the order is not supplied, then the variables are
plotted in default dataset order.
Displaying a PCP plot with coloured panels
cparcoord is a versions of
cparcoord(longley, order= longley.o,panel.color= longley.color,
horizontal=TRUE, mar=c(2,4,1,1))
Plotting re-ordered dendrograms.
eurodist is a built-in distance matrix giving the
distance between European cities.
par(mar=c(1,1,1,1))
data(eurodist)
dis <- as.dist(eurodist)
hc <- hclust(dis, "ave")
plot(hc)