Synopsis
		sfderiv < in.rsf > out.rsf order=6 scale=n

May 2012 program of the month:
http://ahay.org/rsflog/index.php?/archives/290-Program-of-the-month-sfderiv.html

Parameters
		int order=6 filter order   bool scale=n [y/n] if scale by 1/dx

Used In
		GEO384W          hw3/synth hw4/synth   JSG          lowrank/fio nmo3/azimuthtest oc3/french oc3/frenchint pmig/mig pmig/nmo reversible/nscnmo   MILANO          taupvel/cmp taupvel/synth   RSF          rsf/sfderiv su/rsflab8   SEP          oc2/cup   SWAG          tau/hess tau/lens tau/marm