A more specific example would be to use
**sufind** to look for dip moveout (DMO) programs:

% sufind dmo SUDMOFK - DMO via F-K domain (log-stretch) method for common-offset gathers sudmofk <stdin >stdout cdpmin= cdpmax= dxcdp= noffmix= [...] SUDMOTX - DMO via T-X domain (Kirchhoff) method for common-offset gathers sudmotx <stdin >stdout cdpmin= cdpmax= dxcdp= noffmix= [optional parms] SUDMOVZ - DMO for V(Z) media for common-offset gathers sudmovz <stdin >stdout cdpmin= cdpmax= dxcdp= noffmix= [...] SUFDMOD2 - Finite-Difference MODeling (2nd order) for acoustic wave equation sufdmod2 <vfile >wfile nx= nz= tmax= xs= zs= [optional parameters] SUSTOLT - Stolt migration for stacked data or common-offset gathers sustolt <stdin >stdout cdpmin= cdpmax= dxcdp= noffmix= [...]The last two ``hits'' are spurious, but we see that three DMO programs have been found.

Now use the self-doc facility to get more information about **sudmofk**:

% sudmofk SUDMOFK - DMO via F-K domain (log-stretch) method for common-offset gathers sudmofk <stdin >stdout cdpmin= cdpmax= dxcdp= noffmix= [...] Required Parameters: cdpmin minimum cdp (integer number) for which to apply DMO cdpmax maximum cdp (integer number) for which to apply DMO dxcdp distance between adjacent cdp bins (m) noffmix number of offsets to mix (see notes) Optional Parameters: tdmo=0.0 times corresponding to rms velocities in vdmo (s) vdmo=1500.0 rms velocities corresponding to times in tdmo (m/s) sdmo=1.0 DMO stretch factor; try 0.6 for typical v(z) fmax=0.5/dt maximum frequency in input traces (Hz) verbose=0 =1 for diagnostic print Notes: Input traces should be sorted into common-offset gathers. One common- offset gather ends and another begins when the offset field of the trace headers changes. The cdp field of the input trace headers must be the cdp bin NUMBER, NOT the cdp location expressed in units of meters or feet. The number of offsets to mix (noffmix) should typically equal the ratio of the shotpoint spacing to the cdp spacing. This choice ensures that every cdp will be represented in each offset mix. Traces in each mix will contribute through DMO to other traces in adjacent cdps within that mix. The tdmo and vdmo arrays specify a velocity function of time that is used to implement a first-order correction for depth-variable velocity. The times in tdmo must be monotonically increasing. For each offset, the minimum time at which a non-zero sample exists is used to determine a mute time. Output samples for times earlier than this mute time will be zeroed. Computation time may be significantly reduced if the input traces are zeroed (muted) for early times at large offsets. Trace header fields accessed: ns, dt, delrt, offset, cdp.By using

John Stockwell 2007-04-10