PHP Round() not working properly - php

Question

I need help. I'm doing this:
round($myvar,2);
And this is the number I'm getting: 9.779999999999999€
With the other variables it works just fine, any idea how to fix this?

Answer 1

I did this:
<?php echo round(9.7752,2);?>
And I got: 9.779999999999999
I believe it's something in php.ini as #MarkBaker said..
But, I fixed it by doing:
<?php echo number_format($myvar,2);
And I got exactly what I wanted.
Thanks guys for the help!

Answer 2

what problem I encounter is that round(18.203,2) = 18.2 ,then json_encode(...) = 18.199999999 .
so I find the solution is json_encode(strval(round(18.203,2))) = 18.2
it works

Answer 3

Just join empty string before round function like
$val = "" . round(9.597466245, 2);

Answer 4

something (could be in some 3rd party code ?) set your ini setting precision to 16
$php -a
php > echo ini_get("precision");
14 // default
php > echo round(9.7752,2);
9.78
php > echo ini_set("precision", 16);
14
php > echo round(9.7752,2);
9.779999999999999

Answer 5

Although OP solved his issue, I saw this while searching for other (but similar) issue.
If you came here with a problem where PHP's round() function is misbehaving (i.e. round(1.4447, 2) will output 1.44 instead of 1.45) that's because round looks just 1 decimal position away from the needed precision, here's a small recursive helper function that solves the issue:
function roundFloat($float, $neededPrecision, $startAt = 7)
{
if ($neededPrecision < $startAt) {
$startAt--;
$newFloat = round($float, $startAt);
return roundFloat($newFloat, $neededPrecision, $startAt);
}
return $float;
}
Usage example:
roundFloat(1.4447, 2, 5); // Returns 1.45
Explanation:
In example above, it starts rounding from 5th decimal point (0) in this case since not stated otherwise.
You can call the function like roundFloat(1.4447, 2, 15) with same
outcome for given float 1.4447.
$startAt just defines the starting point for the "rounding process" or the required precision.
Note: all programming languages have issues with writing some floats precisely (has to do with binary, google that for more info).
Hope it helps someone.

Answer 6

Just encase the result in a floatval
floatval(round($myvar,2));
If you use number_format, you must add the next two parameters otherwise larger numbers will go wrong:
number_format($myvar,2, '.', '');
This tells PHP to use "." as the decimal separator and no thousands separator.

Answer 7

I had the same problem and my workaround (in order to not change the ini-file and possibly break something else):
$rounded = bcdiv($number, 1, 2);

Answer 8

Combining #PabloCamara's answer and the comment from #LorienBrune, this solution worked for me:
function roundFixed($number, $decimalPlaces)
{
return str_replace(',', '', number_format($number, $decimalPlaces));
}