[GRASS-user] r.mapcalc and g.region

[BLANDENIER Lucien]

Hello,

I'm wondering how does r.mapcalc compute the value of a new pixcel if the resolution have been reduced before (i.e. the pixcel is larger). Is it an average ?

I did a simple test with a 10*10 pixcel raster. I reduced the resolution to 5*5 and made a new raster with r.mapcalc "newrast=oldrast*1" but the result was not an average but the higher value of the four underlying pixcels.

I did then the same operation with a more coarser resulution and it seemed to be ok.

Could someone explain this?

Thanks