a small.. note on notation (forgive the pun).
It is said that Poincare' once stated that a good notation system takes
you already halfway toward the solution of your problem. I cannot place
a reference on this, but I'm quite sure it is correct in meaning, if not
in verbatim expression.
I also happen to share strongly - from many a personal experience -
Poincare's opinion.
Greetings from polluted Milano,
Michele Fanelli