Program sfheatimplitest | Solving 1-D heat equation using implicit finite difference 
[SYNOPSIS]
sfheatimplitest > out.rsf nt= dt= nx= dx=
[COMMENTS]
\partial(u)/\partial(t)=a^2\partial^2(u)/\partial(x^2), 0<x<l & t>0,
u(0,t)=u(l,t)=0, t>0, 
u(x,0)=f(x), 0<=x<=l.  
[PARAMETERS]
float   | dt | = |   | 	temporal sampling 
float   | dx | = |   | 	spatial sampling 
int     | nt | = |   | 	number of temporal points 
int     | nx | = |   | 	number of spatial points 
[DIRECTORY]
user/chenyk
