my $cmp2 = $embedding->comparator($embed2);
# classify target embeddings according to which they are most similar to
for my $next_embed (@targets) {
  my $diff1 = $cmp1->($next_embed);
  my $diff2 = $cmp2->($next_embed);
  if ($diff1 > $diff2) {
    push @closer_to_embed1, $next_embed;
  } else {
    push @closer_to_embed2, $next_embed;
  }
}