Synopsis
		sfpwsmooth < inp.rsf dip=dip.rsf > out.rsf verb=n eps=0.01 ns= bilat=n gauss=n ax= bx=

Parameters
		float ax= Gaussian weight for the range distance   bool bilat=n [y/n] if y, bilateral smoothing   float bx= exponential weight for the domain distance   file dip= auxiliary input file name   float eps=0.01 regularization   bool gauss=n [y/n] if y, gaussian weight; otherwise, triangle weight   int ns= spray radius   bool verb=n [y/n] verbosity