I try to solve a stiff non-linear ODE including a time-dependent term with ode15s (and I tried others too) using mass matrix. Matlab starts computing but then displays a warning and aborts:
Warning: Failure at t=4.691305e-05. Unable to meet integration tolerances
without reducing the step size below the smallest value allowed
(1.084202e-19) at time t.
Does anybody have an idea how to avoid this?