comp.pl

#!/usr/bin/perl
use POSIX;
use strict;

sub ent1 {
  my ($p) = @_;
  return -$p*log($p)/log(2.0);
}

sub ent {
  my ($p) = @_;
  return ent1($p) + ent1(1-$p);
}

my $f = 0;
my @comp;
my @len;
while (<>) {
  next unless /8 part V0 load (\d+)/;
  my $load = $1;
  my $nc = 3200 * ++$f/100.0;
  my $nunc = 3200-$nc;
  my $p = ($load-$nunc)/$nc;
  my $e = ent($p);
  $comp[$f] = $e;
  # printf("%2d %4d %3.4lf %3.4lf\n",$f,$load,$p,$e);
  printf("(%2d,%0.4lf)%s",$f, $e, $f % 5 ? " " : "\n");
}
for my $mp (19..99) { # memory percentage
  printf("\nmp = %2d ",$mp);
  my $i;
  my $np = $mp;   # nonce percentage
  for ($i=0; $np < 100;  $i++) {
    my $c = $comp[$mp];
    $np += (1-$c)*$mp;
    $np = int($np);
  }
  $len[$mp] = $i;
  # printf("%2d %3d",$mp, $i);
}
for my $tot (25..100) { # memory percentage
  my $best=999999;
  my $bmp;
  for my $mp (19..$tot-1) { # memory percentage
    my $cost = $len[$mp] * 16*int(ceil(200/($tot-$mp)));
    next unless $cost < $best;
    $best = $cost;
    $bmp = $mp;
  }
  printf("(%2d,%3d)%s",$tot, $best, $tot % 5 ? " " : "\n");
  # printf("(%2d,%3d)%c",$tot, $bmp, $tot%5?" ":"\n");
}
print "\n";