NAME

Bandpass,Lpfilt - Bandpass dataset


SYNOPSIS

       Bandpass <in.H  flo=0. fhi=0.5/dt
                 nplo=6 nphi=6 phase=0 > out.H
       Lpfilt <in.H  f3db= order=6  > out.H


INPUT PARAMETERS

flo,fhi,f3db - real
         low and high cutoff frequencies;
         flo for lowcut filter (no default); fhi=[0.5/dt] for highcut;
             gain at flo and fhi is: -6db for zero-phase filter
                                -3db for minimum-phase filter. flo and f3db are equivalent
nplo,nphi,order - integer
        number of poles for low and high cutoffs;
            filter roll-off rate is proportional to number of poles 
      (order,nplo are equvilant)
phase - integer
         [0]: for zero-phase; =1 for minimum-phase


DESCRIPTION

Butterworth bandpass filter.


EXAMPLED

       Bandpass <in.H in=stdin out=stdout flo=0. fhi=0.5/dt
                                    nplo=6 nphi=6 phase=0 > out.H


REFERENCE

Technical reference: Oppenheim, A.V., and Schafer, R.W., 1975, Digital signal processing, Prentice-Hall Inc.


SEE ALSO

the Lpfilt manpage


CATEGORY

seis/filter