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run code in 300+ PHP versions simultaneously
<?php $mynumber = (float) "3.8e-7"; var_dump($mynumber); printf('%.90F', $mynumber);
Output for 5.3.4 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.31, 7.4.0 - 7.4.25, 7.4.27 - 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
float(3.8E-7) Notice: printf(): Requested precision of 90 digits was truncated to PHP maximum of 53 digits in /in/qqJ3W on line 5 0.00000038000000000000001456801801587304101559539049049
Output for 7.3.32 - 7.3.33, 7.4.26
float(3.8E-7) 0.00000038000000000000001456801801587304101559539049049
Output for 5.2.9 - 5.2.17, 5.3.0 - 5.3.3
float(3.8E-7) Notice: printf(): Requested precision of 90 digits was truncated to PHP maximum of 40 digits in /in/qqJ3W on line 5 0.0000003800000000000000145680180158730410
Output for 5.2.1 - 5.2.8
float(3.8E-7) 0.0000003800000000000000145680180158730410
Output for 4.3.10 - 4.3.11, 4.4.0 - 4.4.9, 5.0.3 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0
float(3.8E-7) 0.0000003800000000000000710542735760100186
Output for 4.3.0 - 4.3.9, 5.0.0 - 5.0.2
float(3.8E-7)

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