Program sfrotater | Roatation with Interpolation from a regular grid in 2-D. 
[SYNOPSIS]
sfrotater < inp.rsf > out.rsf angle=90. interp=
[PARAMETERS]
float   | angle | =90. |   | 	rotation angle 
string  | interp | = |   | 	[n,l,c] interpolation type 
[DIRECTORY]
user/zone
