The model builder is used to modify Curve Numbers (CN-values) assigned to individual grid cells of the raster based rainfall/runoff model.
In principle, the CN-values for this model are based on "hydrological soil classes". The classes are predefined, and their extent has been outlined under ArcView GIS. The present version of the model builder is limited to modifying the CN-values for individual classes. The code (number) and the description of the classes can not be edited through this interface.
For the purpose of editing the values, the table is copied to a temporary table.
Pressing the "exit key" will exit the form without saving.
Pressing the "save key" will save the table values and exit.
Editing CN-values for surface runoff is functioning the same way, but uses a different form and table