NAME

     ptop - finds and outputs the first occurence of a  specified
     pressure.

SYNOPSIS

     ptop [-N ntap] [-O otap] [-pval  pval]  [-mode  mode]  [-hw1
     hw1] [-hw2 hw2] [-V] [-?]  [-h]

DESCRIPTION

     ptop reads a pressure or pressure gradient dataset (or velo-
     city model for that matter...) and extracts the depth of the
     first occurence of a specified  pressure  or  gradient.  The
     output  is  a 3 column ascii file (X Y Z), where X and Y are
     any two trace indices and  Z  is  the  depth  to  the  first
     occurence of the pressure.

  Command line arguments
     -Nntap
          Enter the name of the input dataset.

     -Ootap
          Enter the name of the output ascii dataset.

     -pval pval
          Enter the value to locate.

     -mode mode
          Enter the mode (1=first occurrence; 2= deepest top).

     -hw1 hw1
          Enter the first header index mnemonic to output.

     -hw2 hw2
          Enter the second header index mnemonic to output.

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

     -?   Enter this (or '-?' if you are running in  c-shell)  to
          get  online  help.   The  program  will terminate after
          printing this.

     -h   Enter this option to get online help.  The program will
          terminate after printing this.

SEE ALSO

     pptrnehz, ppetn, ppg2psi, psi2ppg, ppfilt,  psifilt3,  ptop,
     fillhdr, gradfilt, mshowray

BUGS

     None known.

AUTHORS

     N. D. Whitmore, Jr., Mary Ann Thornton, M. L. Albertin.

COPYRIGHT

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