update_total_iters()

sub update_total_iters
{
    my $state = shift;

    # $r is the result of this scan.
    my $r = $state->idx_slice();
        # return $self->main()->scans_data()->slice(":,".$self->scan_idx())

    # Add the total iterations for all the states that were solved by
    # this scan.
    $state->main()->add('total_iters',
        PDL::sum((($r <= $state->quota()) & ($r > 0)) * $r)
    );

    # Find all the states that weren't solved.
    my $indexes = PDL::which(($r > $state->quota()) | ($r < 0));

    # Add the iterations for all the states that have not been solved
    # yet.
    $state->main()->add('total_iters', ($indexes->nelem() * $state->quota()));

    # Keep only the states that have not been solved yet.
    $state->main()->scans_data(
        $state->main()->scans_data()->dice($indexes, "X")->copy()
    );
}