awk '
BEGIN {
intermed="false"
}
 { 
segment=$3


if ( segment == oldsegment ) {
     if ( intermed == "true" ) printf"%12.3f%12.3f              7\n",oldx,oldy
      else {
 printf"%12.3f%12.3f              6\n",oldx,oldy
 intermed="true"
  }
   }
else if ( intermed == "true" ) {
     intermed="false"
     printf"%12.3f%12.3f              8\n",oldx,oldy
     }
   else printf"%12.3f%12.3f              9\n",oldx,oldy
oldsegment=segment
oldx=$1
oldy=$2
}
END {
printf"%12.3f%12.3f              8\n",oldx,oldy
} ' $1 | tail +3 > $1.fix