[R] Creating a Polar Plot with expanding points as radius increases

[Patrick Jemison]

I'd like to create a polar plot similar to those created by the polarFreq
function in the openair package.  However, this package seems to be specific
to wind speed and direction, and requires a "ws" (wind speed) and a "wd"
(wind direction) column.  My data is unrelated to wind speed, but I'd like
to be able to get a plot that does what polarFreq's plots do; I'd like to
have points that expand as their distance from the center increases.

http://www.oga-lab.net/RGM2/func.php?rd_id=openair:polarFreq

Without this property, my plot looks more like spokes on a wheel, or similar
to the polar.plot function in the plotrix package:
http://www.oga-lab.net/RGM2/func.php?rd_id=plotrix:polar.plot

Is there a package or function available that allows the creation of a plot
as described above for a generic set of polar data?  I spent a few hours
today trying to find something I could use, but no luck yet.

I'm using data of the form: x = r, y = theta, and z = a value to plot at the 
corresponding r,theta (as a comparison, for the polarFreq plot, z would be
the frequency that is indicated by various colors in the plot).

I appreciate any help!

Patrick Jemison