SUFFT - fft real time traces to complex frequency traces		

 suftt <stdin >sdout sign=1 						

 Required parameters:							
 none									

 Optional parameters:							
 sign=1			sign in exponent of fft			
 dt=from header		sampling interval			
 verbose=1		=0 to stop advisory messages			

 Notes: To facilitate further processing, the sampling interval	
 in frequency and first frequency (0) are set in the			
 output header.							

 sufft | suifft is not quite a no-op since the trace			
 length will usually be longer due to fft padding.			

 Caveats: 								
 No check is made that the data IS real time traces!			

 Output is type complex. To view amplitude, phase or real, imaginary	
 parts, use    suamp 							

 Examples: 								
 sufft < stdin | suamp mode=amp | .... 				
 sufft < stdin | suamp mode=phase | .... 				
 sufft < stdin | suamp mode=real | .... 				
 sufft < stdin | suamp mode=imag | .... 				


 Credits:

	CWP: Shuki Ronen, Chris Liner, Jack K. Cohen

 Note: leave dt set for later inversion

 Trace header fields accessed: ns, dt
 Trace header fields modified: ns, d1, f1, trid