Have you tried the function over() from the sp package to extract the
values and then compute the average? I used it to extract the values from a
larger SpatialPixelsDataFrame to a smaller one and then computer my
average.

On Sat, Dec 22, 2012 at 3:00 AM, <r-sig-geo-request@r-project.org> wrote:

> Mean of SpatialGridDataFrames or SpatialPixelsDataFrames
>       (Baalam Kan)
>



-- 
Katherine Lockhart
Graduate Student Researcher
UC Davis
Department of Land, Air, and Water Resources

	[[alternative HTML version deleted]]

