3v4l.org

run code in 300+ PHP versions simultaneously
<?php $arr = [0.12345,0.012345,0.0001239,0.0001209]; Foreach($arr as $val){ Preg_match("/([0\.]+)([0-9]+)/", $val, $match); Echo $match[1]. Substr(round("0.".$match[2],3),2,3)."\n"; }
Output for 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.27, 8.4.1 - 8.4.14
0.123 0.0123 0.000124 0.000121

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146.76 ms | 407 KiB | 5 Q