ordipointlabel produces ordination plots with
points and text label to the points. The points are in the exact
location given by the ordination, but the function tries to optimize
the location of the text labels to minimize overplotting text. The
function may be useful with moderately crowded ordination plots.ordipointlabel(x, display = c("sites", "species"), choices = c(1, 2),
col = c(1, 2), pch = c("o", "+"), font = c(1, 1),
cex = c(0.8, 0.8), add = FALSE, ...)display.ordipointlabel with items xy for coordinates of
points, labels for coordinates of labels, items pch,
cex and font for graphical parameters of each point or
label. In addition, it returns the result of optim as
an attribute "optim". The unit of overlap is the area
of character "m", and with variable cex it is the
smallest alternative. The result object inherits from
orditkplot result, and can be replotted with its
plot command. It may be possible to further edit the result
object with orditkplot, but for good results it is
necessary that the points span the whole horizontal axis without empty
margins.optim,
method = "SANN") to optimize the location of the text labels
to the points. There are eight possible locations: up, down, sides
and corners. There is a weak preference to text right above the
point, and a weak avoidance of corner positions. The exact locations
and the goodness of solution varies between runs, and there is no
guarantee of finding the global optimum. The optimization can take a
long time in difficult cases with a high number of potential
overlaps. Several sets of scores can be displayed in one plot. The function is modelled after pointLabel in
S4
packages).
pointLabel for references.pointLabel for the model
implementation, and optim for the optimization.data(dune)
ord <- cca(dune)
ordipointlabel(ord)Run the code above in your browser using DataLab