Saving an extra variable from PDEPE

Hi, I am solving a heat problem using the PDEPE. Everything is working, however I want to save some extra variables from the main function of the PDEPE that I solve. How can I do this? Adding it to the function handle does not work for me. I want to save the value for Q.

removing the ; indicates that the value is being calculated, but I cannot save it.

function [c,f,s,Q] = heatpde(x_d,t_d,u,dudx,C)

k_d = C.k_d;
STE = C.STE;
w = C.w;
W = C.W;
Cp_d = C.Cp_d;
theta_f = u(1);
y_LS = u(2);
eps = 1e-15;
eps2 = 1e-8;

dtheta_fdx =dudx(1);
d_y_LS_dx =  (1/y_LS)*(dudx(2))+eps2;
q_eff = -k_d*w*dtheta_fdx;
c = [Cp_d/k_d;y_LS;1];
f =[dudx(1);0;0];



s = [-1/(k_d*(w))*(theta_f/y_LS+(STE*theta_f*(theta_f+2*dtheta_fdx/d_y_LS_dx*y_LS))/(6*y_LS) ;...
(theta_f/y_LS+STE*theta_f*(theta_f+2*dtheta_fdx/d_y_LS_dx*y_LS)/(6*y_LS); ...
    -STE^2*theta_f*(40*(dtheta_fdx/d_y_LS_dx)^2*(y_LS)^2+85*theta_f*dtheta_fdx/d_y_LS_dx*y_LS+19*theta_f^2)/(360*y_LS))];


Q = (theta_f/y_LS+STE*theta_f*(theta_f+2*dtheta_fdx/d_y_LS_dx*y_LS))/(6*y_LS);

Answer 1

[Torsten]

After the computation with "pdepe" is completed, call "pdeval" to get the spatial derivatives of your solution on the x-mesh and then call "heatpde" in a loop for all spatial points and times that you like to get Q returned.

[kjell revenberg]

Thankyou! I got it working