"Saad" wrote in message <email@example.com>... > Hi, > I'm trying to solve the following PDE using (pdepe). > Does anyone have any tips on how to input the variable coefficients for this equation. > > dH/dt + 1/sinx d/dx(H^3 (sinx)^2)=0 > > > Thanks, > Saad
pdepe is suited for PDEs which contain a second-order spatial derivative (in your case, this would be an expression involving d^2H/dx^2). Since your equation is a first-order PDE, you will have to solve it using a different tool. Differentiating out, you get dH/dt + 3*H^2*sin(x)*dH/dx = -2*H^3*cos(x).