R help - Nov 2011 - Adding units to levelplot's colorkey

How to add units (e.g. "cm") to the color key of a lattice levelplot?

The plots looks fantastic, but it would be nice to indicate somewhere 
near the end of the color key that the values associated with its colors 
are in centimeters or some other physical units.

The only thing I find is the possibility to specify the labels so that 
one explicitly includes the units.  That leaves little flexibility for 
positioning where this information appears.  Is there a better way?

You don't show code or a reproducible example, so I guess you want a
general answer. Use the draw.colorkey() function inside the
levelplot() call. It takes an argument key =, which accepts a list of
arguments, including space, col, at, labels, tick.number, width and
height (see p. 155 of the Lattice book). More specifically, the labels
argument also accepts a list of values, with components at, labels,
cex, col, font, fontface and fontfamily. You could attach the units as
labels with a combination of at = and labels = inside the (outer)
labels argument, something like

myAt <- c(1, 3, 5, 7, 9)
myLab <- paste(myAt, 'cm')

levelplot( ...
   draw.colorkey(key = list(labels = list(at = myAt, labels = myLab)),
...        )

If that doesn't work, then please provide a reproducible example.

HTH,
Dennis

On Mon, Nov 14, 2011 at 12:34 PM, Carlisle Thacker
<Carlisle.Thacker at noaa.gov> wrote:
> How to add units (e.g. "cm") to the color key of a lattice
levelplot?
>
> The plots looks fantastic, but it would be nice to indicate somewhere near
> the end of the color key that the values associated with its colors are in
> centimeters or some other physical units.
>
> The only thing I find is the possibility to specify the labels so that one
> explicitly includes the units. ?That leaves little flexibility for
> positioning where this information appears. ?Is there a better way?
>
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