Loss of information needed for analysis after conversion

Discussion created by johardstaff on Sep 24, 2010
Hi Everyone,

I needed to change the resolution of my map from 250m to 10km2 but obtain the proportion of landcover within each 10km2 based on 250m data, i.e. % of squares from the 1600 (250m) land cover squares nested within each 10km cell.
I was told to conver my raster maps into feature, which I did and then convert them back into raster (which I've done). I did this using Spatial analysis tool box. I am concerned that not all the data i.e. landcover points are being included.
One of my problems is my map is large and I have been told that I have too many points for a raster attribute table. Is this why when I try to sum the data in each 10km sq using single output map algebra its not working?  My single output map algebra statement is sum([Sp10km], (Grid_code==1), 1,0). The program doesn't acknowledge that Grid_code exists. The points (8 million) retain their information.

Thank you,