I am trying to solve ODEs in matlab using ode15s. Instead of specifying ODEs in the format
M * dC/dt = f(C,t) where C is a function of x and t.
I want to use
M * dC/dt = J*C
Since the vector C is very large I am expecting considerable reduction in computation time. I am trying to figure out how to code the Dirichlet boundary condition C(x=0,t) = a. thanks