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<?php $n = 0 - 0.000000000000000000000000000000001; echo '$n: '; var_dump($n); echo 'round($n): '; var_dump(round($n));
Output for 5.2.1 - 5.2.17, 5.3.0 - 5.3.3, 5.3.7 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.0 - 7.2.33, 7.3.12 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
$n: float(-1.0E-33) round($n): float(-0)
Output for 4.3.3 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0, 5.3.4 - 5.3.6
$n: float(-1.0E-33) round($n): float(0)
Output for 4.3.0 - 4.3.2
$n: float(-1.E-33) round($n): float(0)
preferences:
216.06 ms | 401 KiB | 356 Q