nSweep is a computer program written in Matlab for numerically solving multi-spin Hamiltonians. In particular, it was originally designed to make easy the problem of simulating a sequence of pulses which are themselves linked to the control fields of the Hamiltonian. Feel free to download the nSweep package here along with a few example pieces of code to get you started. Below are some sample screenshots from the program.
This code was written by myself and Samuel Gorman whilst at The University of New South Wales.