I'm solving a nonlinear pde system in one space. It looks that the pdepe function won't work, because it only accepts coupled term in 's', not 'c' and 'f'. My equations are like: \partial u1\partial t + c(u2)*\partial u2\partial t = f1(u2)*D^2 u1Dx^2 + s1(u1,u2); \partial u2\partial t = f2*D^2 u2Dx^2 + s2(u1,u2); So instead of a column vector for 'c', which is required in pdepe function description, I have a non-diagonal 'c' matrix. Does anybody has any idea? Thanks!