$_[0] / 1000 ** $unit, # number
$float ? 0 : 3, # unit size
$#{$opt{units}} >> 1 < abs $unit ? "e$unit" : $opt{units}->[$unit]
$_[0] / 1000 ** $unit, # number
$float ? 0 : 3, # unit size
$#{$opt{units}} >> 1 < abs $unit ? "e$unit" : $opt{units}->[$unit]