Burgers' equation with a transonic rarefaction wave.

Comparison of results obtained with or without the entropy fix.
This is set in the Riemann solver by modifying the variable efix
and recompiling.

Note: also try changing mx to an odd value (e.g. 61 instead of 60).
Then there is one grid cell with the value 0.5 at x=0 and a different
weak solution is obtained.



WARNING: This example was modified February, 2006 to use
Version 4.3 of clawpack and the associated matlab scripts.