On Jan 31, 2006, at 5:37 PM, Van Thinh Nguyen wrote: > Hi all, > > When I read Chapter 2 on Discretization and Algorithm, at the eq. > (2.15); a linearization of free-surface equation; I saw on the RHS > = P-E+R; Could someone explain for me what P, E and R instead of? i would guess Precipitation Evaporation Rivers Good night