Strange behaviour with arithmetic operations

Asked Dec 19 '16 at 09:43

Active Dec 19 '16 at 09:43

Viewed 22 times

I have following code for example:

<?php

print 1 - 0.8 - 0.2 . PHP_EOL;

print 1 - 0.2 - 0.8 . PHP_EOL;

print 1 - 0.2 . PHP_EOL; 

print 1 - 0.8 . PHP_EOL;

print 0.2 - 0.2 . PHP_EOL;

And after execution it has output:

-5.5511151231258E-17
0
0.8
0.2
0

How did -5.5511151231258E-17 ? Why? I am confused...

Example link: http://sandbox.onlinephpfunctions.com/code/bc4c31db76fa9746d76e8ac7ac4042777e095b81

asked Dec 19 '16 at 09:43

Viktor Kulikov

You do understand that `-5.5511151231258E-17` stands for `-0.000000000000000055511151231258`? – deceze Dec 19 '16 at 09:59
@deceze Yes, but i want to understand why) Thx for link to duplicate! – Viktor Kulikov Dec 19 '16 at 10:16

Strange behaviour with arithmetic operations

0 Answers0