Initial data for the exact solution subroutine p_smooth/u_exa.f:

3.		maximum temperature 'umax' in the bar.
1.		steepening parameter 'alpha' for the initial profile.
1.		shift parameter 'beta' for the initial profile

The initial profile takes the form
	u = umax arctan(alpha sin(2 pi x/l -beta)) / arctan(alpha)
hence for
	alpha = 0:		u(x,0) = umax sin(2 pi x/l - beta)
	alpha = infinity:	u(x,0) = +umax or -umax

Copyright 1996 Leon van Dommelen