method
either "bray" (for the Bray-Curtis distance) or
"aitchison" (for Aitchison's central logratio distance). If
omitted, the function defaults to 'aitchison', unless there are
zeros present in the data.
colmap
an optional string with the name of one of R's
built-in colour palettes (e.g., heat.colors, terrain.colors,
topo.colors, cm.colors), which are to be used for plotting the data.