I looking for some advice in how to construct a conditional statement to generate a New Flow Accumulation Grid where it intersects a Railway Alignment Polyline that I have converted into a raster grid. The problem that I have is that I don't know before hand the range of values that I'll be dealing with and the New Flow Accumulation Grid needs to be the result where the two grids intersect. Any advice to constructing a conditional statement will be appreciated.
Regards
