Program sfaps3d | 3D acoustic wavefield modeling using the pseudo-spectral method  
[SYNOPSIS]
sfaps3d < Fi.rsf > Fo.rsf dat=Fd.rsf dat_v=Fd_v.rsf snaps=snaps.rsf spx= spy= spz= f0= t0= A= jsnap=0 cmplx=y pad1=1 abc=n nbt= nbb=nbt nblx=nbt nbrx=nbt nbly=nbt nbry=nbt ct= cb=ct clx=ct crx=ct cly=ct cry=ct verb=n ps=n tri=n vref=1500 nt= dt= gplx=-1 gply=-1 gpl_v=-1 src=0 ns=1 gpx=-1 gpy=-1 gpz=-1 gpx_v=-1 gpy_v=-1 gpz_v=-1
[COMMENTS]
DEMO:
https://github.com/chenyk1990/tutorials/blob/main/demo/aps3d/SConstruct

[PARAMETERS]
floats  | A | = |   | 	wavelet amplitude  [ns]
bool    | abc | =n |  [y/n] | 	absorbing flag 
float   | cb | =ct |   | 	
float   | clx | =ct |   | 	
float   | cly | =ct |   | 	
bool    | cmplx | =y |  [y/n] | 	use complex fft 
float   | crx | =ct |   | 	
float   | cry | =ct |   | 	
float   | ct | = |   | 	
string  | dat | = |   | 	auxiliary input file name
string  | dat_v | = |   | 	auxiliary input file name
float   | dt | = |   | 	
floats  | f0 | = |   | 	wavelet peak freq  [ns]
int     | gpl_v | =-1 |   | 	geophone height 
int     | gplx | =-1 |   | 	geophone length X
int     | gply | =-1 |   | 	geophone length Y
int     | gpx | =-1 |   | 	geophone position x 
int     | gpx_v | =-1 |   | 	geophone position x 
int     | gpy | =-1 |   | 	geophone position y 
int     | gpy_v | =-1 |   | 	geophone position y 
int     | gpz | =-1 |   | 	geophone position z 
int     | gpz_v | =-1 |   | 	geophone position z 
int     | jsnap | =0 |   | 	interval for snapshots 
int     | nbb | =nbt |   | 	
int     | nblx | =nbt |   | 	
int     | nbly | =nbt |   | 	
int     | nbrx | =nbt |   | 	
int     | nbry | =nbt |   | 	
int     | nbt | = |   | 	
int     | ns | =1 |   | 	source type 
int     | nt | = |   | 	
int     | pad1 | =1 |   | 	padding factor on the first axis 
bool    | ps | =n |  [y/n] | 	use pseudo-spectral 
file    | snaps | = |   | 	auxiliary output file name
ints    | spx | = |   | 	shot position x  [ns]
ints    | spy | = |   | 	shot position y  [ns]
ints    | spz | = |   | 	shot position z  [ns]
int     | src | =0 |   | 	source type 
floats  | t0 | = |   | 	wavelet time lag  [ns]
bool    | tri | =n |  [y/n] | 	if choose time reversal imaging 
bool    | verb | =n |  [y/n] | 	verbosity 
float   | vref | =1500 |   | 	reference velocity (default using water) 
[DIRECTORY]
user/chenyk
