QUBIT4MATLAB is a MATLAB package for quantum information/quantum optics written by Geza Toth. It has more than 6000 downloads!
If you use it for a publication, please add a citation like the following to your paper
[1] G. Toth, Comput. Phys. Comm. 179, 430 (2008).
This program package helps modelling spin chains, qubit registers, etc. according to non-relativistic quantum mechanics and some novel ideas from quantum information theory.
In particular, it contains MATLAB routines for reordering qubits, for computing the reduced density matrix after removing some of the qubits, for partial transposition, etc. Most of the routines work also for qudits. It also has routines for handling GHZ states, cluster states, graph states, Dicke states, etc.
For the list of functions write
help contents_qubit4matlab
or
helpwin contents_qubit4matlab
or
type contents_qubit4matlab
For examples see
example1
example2
example3
For the description of the program see Intro.
Download QUBIT4MATLAB V6.4 from MATLAB central file exchange
Local archive
Download QUBIT4MATLAB V6.4 (LATEST VERSION)