function P = rhs(A)% residual.m Nonlinear equation model object residual update.%% INPUT/OUTPUT PARAMETERS%        A : an object derived from the neqmodel class%% Copyright (c) by Raymond A. Adomaitis, 1998-2007unpack(A,'var')unpack(A,'param')v = velocity(A);ResT = gradient(v*RSF) - h*RSF*(Ts-T);ResT = setval(ResT, getval(T,1) - Tamb, 1); % BC residualResxA = gradient(xA) + RSF*(1/T)*k1*exp(-E1/T)*xA;ResxA = setval(ResxA, getval(xA,1) - xAo, 1); % BC residualResxB = gradient(xB) - RSF*(1/T)*k1*exp(-E1/T)*xA ...        + RSF*(1/T)*k2*exp(-E2/T)*xB;ResxB = setval(ResxB, getval(xB,1) - xBo, 1); % BC residualResxC = gradient(xC) - RSF*(1/T)*k2*exp(-E2/T)*xB + RSF*kd*xC;;ResxC = setval(ResxC, getval(xC,1) - xCo, 1); % BC residualP = {ResT ResxA ResxB ResxC};