search for: geographyc

Hi, I'm interpolating a list of syncronous accumulated precipitation observations collected over a number of raingauge stations sited over land, over a regular lat/lon grid using akima's interp(). Then, I plot and locate geographycally the resulting field with a filled.contour() and a call to map(). Everything is fine but I need to "blank" (in Golden Surfer nomenclature) the areas of my domain that lay over the sea, as I do not have observations there and structures are completely artificial. Is there any funct...