Program sfupgrad | Causal gradient operator 
[SYNOPSIS]
sfupgrad < inp.rsf ref=ref.rsf > out.rsf adj=n grad=y dim=
[PARAMETERS]
bool    | adj | =n |  [y/n] | 	adjoint flag 
int     | dim | = |   | 	
bool    | grad | =y |  [y/n] | 	if y, gradient; if n, Laplacian 
file    | ref | = |   | 	auxiliary input file name
[DIRECTORY]
user/fomels
