sum inside if statement in PHP [duplicate]

Question

somebody can explain me why this code:

$a = 0.1;
$b = 0.2;

if ($a + $b == 0.3) {
    echo "OK";
} else {
    echo "KO";
}

returns KO?

I don't understand why the sum result is different the float 0.3, considering that:

var_dump($a + $b);

returns: float(0.3)

The only hypothesis I have is that the comparison is made between only $b and 0.3 but the doubt remains because also in this case:

if ( ($a + $b) == 0.3) {

I get KO..

If you set the precision than the comparison will be done, otherwise not. — Murad Hasan
– Murad Hasan, Commented May 30, 2016 at 9:00
http://php.net/manual/en/language.types.float.php#113703 answers perfectly to the question. Thanks — suikoy
– suikoy, Commented May 30, 2016 at 9:13

Murad Hasan · Accepted Answer · 2016-05-30 09:04:41Z

0

This is a floating point number and the precision of this number is not fixed, if you fixed the precision than it will be okey.

$a = 0.1;
$b = 0.2;
$c = sprintf('%.1f', ($a + $b));
if ($c  == 0.3) {
    echo "OK";
} else {
    echo "KO";
}

the result is OK now.

answered May 30, 2016 at 9:04

Murad Hasan

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Comments

Pudich Denis · Accepted Answer · 2016-05-30 09:10:30Z

0

Use function round($a+b, 1); I have this problem in my code

answered May 30, 2016 at 9:10

Pudich Denis

11