Rewrite calculate_MI_bounded_discrete to avoid repeating computation.
Rewrite calculate_MI_bounded_discrete to avoid repeating computation.

(Also choose more descriptive variable names).

mit-probabilistic-computing-project/crosscat,mit-probabilistic-computing-project/crosscat,mit-probabilistic-computing-project/crosscat,probcomp/crosscat,probcomp/crosscat,mit-probabilistic-computing-project/crosscat,probcomp/crosscat,mit-probabilistic-computing-project/crosscat,probcomp/crosscat,probcomp/crosscat,mit-probabilistic-computing-project/crosscat,probcomp/crosscat,probcomp/crosscat,mit-probabilistic-computing-project/crosscat,probcomp/crosscat