Program sfshifts | Multiple shifts. 
[SYNOPSIS]
sfshifts < inp.rsf > out.rsf np= dp= p0=
[PARAMETERS]
float   | dp | = |   | 	slope sampling 
int     | np | = |   | 	number of slopes 
float   | p0 | = |   | 	first slope 
[DIRECTORY]
system/seismic
