Here you will need a bit of perl (probably can be done in awk, but when you get out of one-line volume of code in awk you want to switch to perl). This takes one parameter (or 4 by default) and text on stdin, like this: ./split.pl 6 < aa.npg > worktodo.txt
Code:
#!/usr/bin/perl -w
$N = (shift || 4);
@A = <>;
for($i=1;$i<=$N;$i++) {
print "[Worker #", $i, "]\n";
for($k=$i;$k<@A;$k+=$N) {
$A[$k] =~ /(\d+) (\d+)/;
print "PRP=$1,2,$2,-1\n";
}
}
Note: this, of course, assumes that the input if an .npg file or a .pfgw file and the first line of it is to be thrown away. Don't forget it or else you will lose the first line with a candidate (if you actually already stripped the header).