Program sfmdfd4 | 2D finite difference modeling	
[SYNOPSIS]
sfmdfd4 < modl.rsf > data.rsf wave=wave.rsf div=div.rsf nt=1000 dt=0.004 jt=40 wvlt=0 w0=35.0 sx=0 sz=0 rx0=0 nr=1 dr=1 rz=0
[PARAMETERS]
file    | div | = |   | 	auxiliary output file name
int     | dr | =1 |   | 	receiver interval of unit "dx" 
float   | dt | =0.004 |   | 	time interval 
int     | jt | =40 |   | 	wave movie time interval 
int     | nr | =1 |   | 	receiver numbers 
int     | nt | =1000 |   | 	time samples 
int     | rx0 | =0 |   | 	x position index of first receiver 
int     | rz | =0 |   | 	z position index of receivers 
int     | sx | =0 |   | 	x position index of the source 
int     | sz | =0 |   | 	z position index of the source 
float   | w0 | =35.0 |   | 	central frequency for ricker/harmonic wavelet 
string  | wave | = |   | 	wavefield movie file (auxiliary output file name)
int     | wvlt | =0 |   | 	wavelet type "ricker/harmonic/other" 
[DIRECTORY]
user/chen
