removing for-loops in ptrace to gain speed.
removing for-loops in ptrace to gain speed.

anubhavvardhan/qutip,qutip/qutip,cgranade/qutip,anubhavvardhan/qutip,zasdfgbnm/qutip,qutip/qutip,cgranade/qutip,zasdfgbnm/qutip