cat and size

What's the appropriate way to get a category
and its corresponding size of area from
a raster layer?

I know r.report will create a list. However,
I want to use the category name (it's a number
in my case) and the size to do a compuation.
It seems to me I have to program a function.

I appreciate any hint.

--Xin Zhuang
zhuang@access.digex.com