NAME

     mrgshot - sum a cube of seismic data distributed over multi-
     ple files having a common file name stem.

SYNOPSIS

     mrgshot [ -Nfile_stem ] [ -Ootap ] [ -Mamaxmem ] [ -S ] [ -V
     ] [ -? ]

DESCRIPTION

     mrgshot sums N  similarly named data sets into one  (N<100).
     All input data sets must have the same number of samples and
     records per file.   The data cannot be piped in  except  for
     the  degenerate  case  of  a  single input file that fits in
     memory. The data can always be piped out.

     mrgshot gets both its data and its parameters  from  command
     line  arguments.  These arguments specify the inputs, output
     and verbose printout, if desired.

Command line arguments

      parameters describing explicitly defined input data

     -N file_stem
          For multiple input files, enter the file  stem  of  the
          systematically  generated input data set file names (as
          generated by routines such as kmod  or  kmask)  immedi-
          ately  after  typing  -N.  Routine mrgshot will augment
          this file stem by adding nfiles  file  extents  of  the
          form          __1,__2,...,99.          Thus          if
          file_stem=/data/data.model, node_count=1  and  npass=3,
          this   program   will   look   for   the  three  files:
          /data/data.model__1,      /data/data.model__2       and
          /data/data.model__3.  Total  number of files  nfiles is
          stored in line header word /fI'MxLnIn'/fR.   Individual
          file  number   ifile  is  stored  in  line  header word
          /fI'MnLnIn'/fR  and  must  match  the  numerical  value
          tacked to the end of file_stem.


     For the degenerate single file case, file_stem  is the input
     file  name. Lineheader values described above do not need to
     be filled out.

     -O otap
          Enter the output data  set  name  or  file  immediately
          after typing -O.  This output file is not required when
          piping the output to another process.  The output  data
          set also requires the full path name (see above).

     -S   If present, input data consists of a single  file  with
          explicit   name   given  by  file_stem  (with  no  name
          augmentation).

     -M amaxmem
          Enter the maximum memory allowed  for  the  program  in
          Megawords. This option may be necessary when sorting to
          large common offset output data sets on the workstation
          or  Cray-XMP  environment.  The  data  may will be read
          through as many times as necessary to  fall  below  the
          memory  constraints.  (Default: amaxmem=64 Megawords on
          the Crays, amaxmem=8 Megawords on the Sparcs).

     -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.

NOTE 1:

     The non-expert user is highly encouraged to use the job sub-
     mission  xwindows  program  samx  to ensure efficient, rela-
     tively error free construction of a complete  Kirchhoff  mbs
     flow using the sammig algorithm.

SEE ALSO

     kmod, kmask

CONTRACT AGREEMENT

     This product is brought to you as a part of the 4th  quarter
     deliverable  (filtering  of  coherent  noise  in  the  depth
     domain) promised by  Research  Agreement  D96-2518  (Seismic
     Signal Analysis). Thank you for your support.

AUTHOR

     Bertrand Duquet (Amoco EPTG, 1996).

COPYRIGHT

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