[GRASSLIST:1947] Map resolution change by totals not idw

[Roy Sanderson]

Dear Grass-list

I have a 1 km resolution raster map in which each cell contains the area of
woodland habitat; from this I'd like to create a 10 km resolution map in
which each cell contains the sum total of all 100 1-km cells in the
original map.  The r.surf.idw functions use inverse distance weighting,
which isn't appropriate in this instance.  Using Grass 5.0.2

Many thanks in advance
Roy