Bug #76876 [Opn->Nab]: Bug

Edit report at https://bugs.php.net/bug.php?id=76876&edit=1 ID: 76876 Updated by: requinix@php.net Reported by: pls-kick-me at yandex dot ru Summary: Bug -Status: Open +Status: Not a bug Type: Bug Package: *General Issues Operating System: Windows/Ubuntu PHP Version: 7.2.9 Block user comment: N Private report: N New Comment: Floating point values have a limited precision. Hence a value might not have the same string representation after any processing. That also includes writing a floating point value in your script and directly printing it without any mathematical operations. If you would like to know more about "floats" and what IEEE 754 is, read this: http://www.floating-point-gui.de/ Thank you for your interest in PHP. Previous Comments: ------------------------------------------------------------------------ [2018-09-13 06:38:55] pls-kick-me at yandex dot ru Description: ------------ Just calculations. At the end of them unexpected result Test script: --------------- $total_vote = 2.9; $points_teaches = [-0.1, -0.1, -0.1, -0.1, -0.1, -0.1, -0.1, -0.1, -0.1, -0.1]; foreach($points_teaches as $point) { $total_vote += $point; } $total_vote += -0.3; $total_vote += -0.3; $total_vote += -0.3; $total_vote += -0.5; $points_p = [-0.05, -0.05, -0.05, -0.05, -0.05 -0.05, -0.05, -0.05, -0.05, -0.05]; $p = 0.0; foreach ($points_p as $points) { $p += $points; } $total_vote += $p; die($total_vote); Expected result: ---------------- $total_vote == 0 Actual result: -------------- $total_vote == -1.1102230246252E-15 ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=76876&edit=1