Algorithmic performance. Time step size and number of iterations for adaptive time stepping scheme. The algorithm typically convergences within four Newton Raphson iterations. For more iterations, the adaptive algorithm automatically decreases the time step size, for example, during the rapid upstroke phase before t =0.05 s and during the repolarization phase between t =0.25s and t =0.32s. For less iterations, the adaptive algorithm automatically increases the time step size, for example during the plateau phase, between t =0.05s and t =0.25 s and during the resting phase after t =0.32 s. The total number of time increments is 1,288, and the overall run time is 51.97 hours, calculated on a single core of an i7-950 3.06 GHz desktop with 12GB of memory.