NAME

     upolf  - module to do 2-component polarization filtering

SYNOPSIS

     upolf [ -Nntap ] [ -Ootap ] [ -nsns ] [ -nene ] [ -rsrs ]  [
     -rere  ]  [  -bnb  ]  [ -cnc ] [ -yny ] [ -ini ] [ -flfl ] [
     -fhfh ] [ -V ] [ -? ]

DESCRIPTION

     upolf does 2-component polarization filtering in the complex
     time  domain  in  contrast  to  pol2 and pol3 which do their
     polarization filtering strictly  in  the  real  time  domain
     using  time  domain gaussian filters.  The polarization pro-
     perties are extracted from the spectral matrix (rather  than
     the  correlation  matrix)  and  are used to filter the input
     signals.

     upolf gets both its data and  its  parameters  from  command
     line  arguments.  These arguments specify the input, output,
     the start and end traces, the filter control parameters, and
     verbose  printout,  if desired.   The line header is checked
     to see that header entry RATTrc has the value 2; if not  the
     program exits.

  Command line arguments
     -N ntap
          Enter the input data set name or  file  if  not  piping
          immediately  after  typing  -N.  The input data must be
          2-component and have the data in multiplexed form (i.e.
          compt  1,  compt  2, compt1, compt 2, ... ).  This data
          may be generated from separate data  sets  using  mergn
          with  a  -m  flag.   This input file should include the
          complete path name if the file resides in  a  different
          directory.  Example -N/b/vsp/dummy tells the program to
          look for file 'dummy' in directory '/b/vsp'

     -O otap
          Enter the output data set name or file  if  not  piping
          immediately  after  typing -O.  The output data will be
          in the same multiplexed form as the input.

     -ns ns
          Enter the start ntuple number.  This and the next entry
          (if given) are different from the usual trace unit fam-
          iliar to standard trace processing.  An  ntuple  refers
          to a bundle of traces of differing source/receiver com-
          ponents.    Default is the first ntuple.

     -ne ne
          Enter the end ntuple number.  Default is the last  ntu-
          ple.

     -rs rs
          Enter start record number.  Default value is the  first
          record.

     -re re
          Enter end record number.  Default value is last record.

     -re nred
          Enter end record number.  Default value is last record.

     -b nb
          Enter width of each passband in  units  of  delta  fre-
          quency  [  df=1./(nsamp*dt),  where  nsamp  = number of
          samples/trace and dt is the sample interval in  seconds
          ].  Default value is 10

     -c nc
          Enter length of the cosine windows in cycles.  A  cycle
          is  the  period  of  the  midpoint  frequency  of  each
          passband, e.g. for low frequencies the windows will  be
          longer than for high frequencies.  Default is 2

     -y ny
          Reject wave type (default ny = 0):

                    =0 surface waves

                    =1 low frequency p-waves

                    =2 low frequency sv-waves

     -fl fl
          Enter low frequency rejection value in  Hz  (valid  for
          ny=1 or ny=2).  Default is 10

     -i ni
          Enter rectilinearity exponent.  Default is 6

     -fh fh
          Enter maximum frequency in Hz to process.   Default  is
          100

     -V   Enter the command line argument '-V' to get  additional
          printout.

     -?   Enter the command line  argument  '-?'  to  get  online
          help.   The program terminates after the help screen is
          printed.

COPYRIGHT

     copyright 2001, Amoco Production Company
               All Rights Reserved

          an affiliate of BP America Inc.