Program sftxrna | Causal t-x or t-x-y nonstationary regularized autoregression. 
[SYNOPSIS]
sftxrna < mat.rsf > flt.rsf pred=pre.rsf a= niter=20 verb=n
[PARAMETERS]
ints    | a | = |   | 	 [mdim]
int     | niter | =20 |   | 	number of iterations 
string  | pred | = |   | 	auxiliary output file name
bool    | verb | =n |  [y/n] | 	verbosity flag 
[DIRECTORY]
user/yliu
