# Copyright 2003 Arnica Resources
# All Rights Reserved
#
# Program Name : thin3d.ak
# Author       : Eric Keyser
# Email        : eric@arnica.ws
#
# You are free to copy and distribute this awk. This permission notice
# must be preserved complete on all complete or partial copies.
#
#awk to thin a SeisX 3D file to every 32nd line


BEGIN { FS = " "; 

# output the first line, it tells the program the number of horizons
printf ("%s\n", $0)
getline
Numcol= $1 + 4;
  }

#Middle
    {
if ( NF == Numcol ) { 
 if ( ($1 % 32) == 0) { printf( "%s\n", $0)}
}
 else { printf ("%s\n", $0)}
}

END {  }