New options for user control of plotting function dotTree

I just added a couple of features to the phytools function dotTree. These come in the form of the two optional arguments x.space and leg.space. These arguments allow, respectively, manual control of the horizontal spacing of the columns in a grid of circles or dots in a visualization of multiple traits. Presently by default these circles have a fixed spacing, which can be too wide when trait values for a relatively small number of traits and a relatively large number of taxa are viewed.

For instance, let's start with a simulated tree & dataset with 50 taxa and 20 character traits:

library(phytools)
tree

## 
## Phylogenetic tree with 50 tips and 49 internal nodes.
## 
## Tip labels:
##  t17, t33, t39, t15, t10, t21, ...
## 
## Rooted; includes branch lengths.

dim(X)

## [1] 50 20

dotTree(tree,X,fsize=0.7)

This looks nice (at least in my unbiased opinion); however if we only plot two or three traits, by contrast, the columns seem over-spaced:

dotTree(tree,X[,1:3],fsize=0.7)

The new argument, x.space, allows us to change the interval over which the columns are spaced:

dotTree(tree,X[,1:3],fsize=0.7,x.space=0.05)

The second new optional argument is leg.space, and this argument allows us to change the spacing on the legend. (I also changed the default value for this setting.)

dotTree(tree,X,fsize=0.7,leg.space=1,length=10)

(The argument length set the number of dots in the legend.)

Note that the argument x.space should also work for data.type="discrete" (the argument leg.space doesn't apply), e.g.:

x

## t17 t33 t39 t15 t10 t21 t45 t36 t31 t35  t3 t16  t1 t37 t18 t34 t49 t27 
## "b" "b" "b" "a" "a" "a" "a" "a" "b" "b" "a" "a" "a" "a" "b" "b" "a" "b" 
## t13 t42 t12 t14 t30 t32 t25 t46 t20 t23 t28 t48 t47  t7 t26  t6  t9  t4 
## "b" "a" "b" "a" "a" "a" "b" "b" "b" "b" "b" "b" "a" "a" "a" "b" "a" "b" 
## t38 t22  t2 t50 t44 t40 t24 t43 t11 t41  t8 t29 t19  t5 
## "a" "a" "a" "a" "a" "b" "a" "a" "a" "b" "a" "a" "a" "b"

y

## t17 t33 t39 t15 t10 t21 t45 t36 t31 t35  t3 t16  t1 t37 t18 t34 t49 t27 
## "c" "d" "c" "c" "d" "c" "c" "c" "c" "d" "d" "d" "c" "c" "d" "d" "d" "c" 
## t13 t42 t12 t14 t30 t32 t25 t46 t20 t23 t28 t48 t47  t7 t26  t6  t9  t4 
## "c" "d" "d" "c" "c" "c" "c" "c" "c" "d" "d" "d" "c" "c" "c" "d" "c" "c" 
## t38 t22  t2 t50 t44 t40 t24 t43 t11 t41  t8 t29 t19  t5 
## "d" "c" "d" "d" "d" "d" "d" "d" "d" "c" "d" "d" "c" "c"

colors<-setNames(palette()[1:4],sort(unique(c(x,y))))
colors

##        a        b        c        d 
##  "black"    "red" "green3"   "blue"

dotTree(tree,cbind(x,y),fsize=0.7,colors=colors) ## the default

dotTree(tree,cbind(x,y),fsize=0.7,colors=colors,x.space=0.05) ## better

The tree & data were simulated as follows:

tree<-rtree(n=50)
X<-fastBM(tree,nsim=20)
Q<-matrix(c(-1,1,1,-1),2,2)
rownames(Q)<-colnames(Q)<-letters[1:2]
x<-sim.history(tree,Q)$states
rownames(Q)<-colnames(Q)<-letters[3:4]
y<-sim.history(tree,Q)$states

That's it.