a) If only one triangle is entered, it divides the off-diagonal
 elements by two and creates the Q matrix from these "halved"
 coefficients.
 b) The entire Q matrix is always doubled before actually storing
 it, whether or not it is "generated" as above or is specified
 completely by the user.
 c) The final Q matrix is then multiplied by -1 before it is used.
 The above does make sense if the reader cares to work the mathematics,
although this is unnecessary as long as the rules are followed. If
the Q matrix arises from cost data, the coefficients should be entered
exactly as they are, (except with positive signs) and only one triangle
of Q should be entered.