NAME

     qstk  - stack the output of TVQE or QEST to generate average
     Q profiles

SYNOPSIS

      qstk [-Nntap] [-Ootap] [-null null] [-opt sum option] [-V ]
     [-h ] [-? ]

DESCRIPTION

     QSTK stacks the output from program tvqe or qest to generate
     average  profiles  for  the input ensembles.  Null values in
     the input traces will be ignored in creating the stack, pro-
     ducing  an  average profile with good S/N and one which will
     correct the phase and amplitude within  the  ensemble  in  a
     uniform manner.

     The program offers two methods of averaging the input  data.
     The  first  is  the standard arithmetic mean, defined as the
     sum of all samples at the same time divided by the number of
     samples  going  into  the  sum.   The  second  method is the
     geometric mean, defined as the Nth root of the running  pro-
     duct  of the N samples in a time slice.  Computation of this
     mean is possible because the data input  are  all  positive.
     The  geometric mean attenuates the effect of "noisy" samples
     on the sum. This is  the  default  and  recommended  summing
     option.   For  both  summing options, only non-zero and non-
     null values are included in the sum.

     Program QSTK makes no  effort  to  correctly  average  trace
     header  values.   If  the  output is to be used for purposes
     other than Q compensation, use program  HDRSWAP  to  replace
     the trace headers with those from a normal ensemble stack.

     QSTK gets both its data and its parameters from command line
     arguments.   These  arguments  specify  the input and output
     file names, the value to be ignored in the sum, and  summing
     option.

  Command line arguments
     -N ntap
          Enter the input data set name or file immediately after
          typing -N unless the input is from a pipe in which case
          the -N entry must be omitted.  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 stacked Output
          Enter the name of  the  stacked  data  set  immediately
          after typing -O.  This output file name is not required
          if piping to another process.   The  output  data  set,
          when  specified,  also requires the full path name (see
          above).

     -null null
          Enter the value of Q to be ingored in summing the data.
          Default = 1000.

     -opt sum option
          Enter "0" to  request  averaging  as  arithmetic  mean.
          Enter  "1"  to request averaging as the geometric mean.
          Default = 1.

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

     -V   Enter the command line argument -V  to  output  verbose
          printout.

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

EXAMPLE

     qstk -Nindata -Oodata -null2000 -opt1

     where the program as been asked to ingore values of 2000 and
     to create the geometric mean as the output.

AUTHOR

        Richard Crider UTG

COPYRIGHT

     copyright 2001, Amoco Production Company
               All Rights Reserved
          an affiliate of BP America Inc.