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defining group colours in a call to rda

2 messages · Andrew Halford, Abby Spurdle

#
Hi,

I've been trying to use the output on group membership of the final leaves
in a MRT analysis to define my own colours, however I am not getting the
result I'm after.

Here is the code
fish.pca <-rda(fish_all.hel,scale=TRUE)
fish.site <- scores(fish.pca,display="sites",scaling=3)
fish.spp <-
scores(fish.pca,display="species",scaling=3)[fish.MRT.indval$pval<=0.05,]
plot(fish.pca,display=c("sites","species"),type="n",scaling=3)
points(fish.site,pch=21,bg=MI_fish_all.mrt$where,cex=1.2)
plotcolor <-
c("red","green","blue","aquamarine","magenta")[MI_fish_all.mrt$where]
 fish.pca <-rda(fish_all.hel,scale=TRUE)
plot(fish.pca,display=c("sites","species"),type="n",scaling=3)
points(fish.site,pch=21,bg=plotcolor,cex=1.2)
MI_fish_all.mrt$where

If I run the points command and insert the group membership direct from the
MRT analysis e.g.  bg=MI_fish_all.mrt$where , then the subsequent points
plot up correctly with a different colour for each group.However if I try
to impose my own colour combo with plotcolor.....It prints colours for 2
groups and leaves the rest uncoloured.

The call to  MI_fish_all.mrt$where gives...
 [1] 3 3 8 6 6 9 5 5 9 3 8 6 9 6 5 9 5 3 8 6 9 6 5 9 5 3 3 8 6 6 9 5 5 9 6
9 5 9.

These are the split groupings for all 39 sites in the analysis and there
are 5 numbers corresponding to 5 final leaves in the tree.

I cant see why my colour scheme isnt being recognised.

All help accepted.

Andy
#
Hi,

Your example is not reproducible.
However, I suspect that the following is the problem:

c("red","green","blue","aquamarine","magenta")[MI_fish_all.mrt$where]

Here's my version:

where = c (3, 3, 8, 6, 6, 9, 5, 5, 9, 3, 8, 6, 9, 6, 5, 9, 5, 3, 8, 6,
9, 6, 5, 9, 5, 3, 3, 8, 6, 6, 9, 5, 5, 9, 6, 9, 5, 9)
unique (where)

c("red", "green", "blue", "aquamarine", "magenta")[where]

There's five colors.
But only two of the indices are within one to five.
So, the resulting color vector contains missing values.

In the base graphics system, if you set colors to NA, it usually means no color.

I'm not sure exactly what you want to do, but I'm assuming you can fix
it from here.
On Tue, Aug 4, 2020 at 9:49 PM Andrew Halford <andrew.halford at gmail.com> wrote: