6

I have some PHP code in a project I'm working on that uses PHP's round function. On my localhost, I don't include any quotes around my mode argument, stating it as just PHP_ROUND_HALF_DOWN. However, when pushing to my server I get the error message:

Use of undefined constant PHP_ROUND_HALF_DOWN - assumed 'PHP_ROUND_HALF_DOWN'
Warning (2): Wrong parameter count for round() [APP/views/helpers/time_left.php, line 14]

Now, when I add the single quotes to the mode argument, the first error goes away, however the "wrong parameter count" remains. I'm calling the function as follows:

$days = round(($difference/$day), 0, PHP_ROUND_HALF_DOWN);

Thanks for any and all help!

Eric
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  • See also [my attempt at a canonical answer for causes of this error message](http://stackoverflow.com/questions/2941169/what-does-the-php-error-message-notice-use-of-undefined-constant-mean/8025500#8025500). – John Carter Nov 06 '11 at 06:46

8 Answers8

11

The mode argument was only added in PHP 5.3.0. If you're running an earlier version of PHP, then the mode option constants (PHP_ROUND_HALF_UP, PHP_ROUND_HALF_DOWN, PHP_ROUND_HALF_EVEN, and PHP_ROUND_HALF_ODD) won't be defined

EDIT

You can't use the mode argument for round() prior to 5.3.0, but you can achieve the equivalent by combining functions:

round(floor($value * 100) / 100,2); //  to round down to 2dp
round(floor($value * 1000) / 1000,3); //  to round down to 3dp
round(ceil($value * 100) / 100,2); //  to round up to 2dp
Mark Baker
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9

The rounding mode was added in PHP 5.3. Make sure you're running at least that version.

You can see which version you're running by placing the following in a PHP file:

var_dump(phpversion());
5

PHP_ROUND_HALF_DOWN requires PHP 5.3.0 as seen here: http://php.net/manual/en/math.constants.php

You're probably on a lower PHP version.

Marwelln
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3

round() defaults to using PHP_ROUND_HALF_UP but you can only change it in PHP >= 5.3.0

To emulate PHP_ROUND_HALF_DOWN I think you can subtract (1/10^(precision+1))*5 from the number before rounding.

to put it simply;

<?php
  $number=20.005;
  $precision=2;
  echo round($number,$precision);                         //20.01
  echo round($number-(1/10^($precision+1))*5,$precision); //20.00
  echo round($number-0.005,2);                            //20.00
?>
Joseph
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2

What version of PHP is running on your server? According to the docs only PHP 5.3 or greater supports the PHP_ROUND constants.

Mr Griever
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2

Is PHP_ROUND_HALF_DOWNsupported by your version?

According to the documentation mode wasnt introduced till 5.3

5.3.0    The mode parameter was introduced.

You can use floor instead (or ceil if you want to go the other way)

Kristoffer Sall-Storgaard
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0

$mode was added on PHP 5.3

check php's version with:

php -v

edit: or use php's phpinfo() procedure

cheers

Wifi Cordon
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0
$qty = 15;
$size = 6;
$box= round(($qty)/($size), 0, PHP_ROUND_HALF_ODD);
$picecs = ($qty)%($size);
echo 'BOX=='.$box. 'PICECS==='.$picecs;
Mohammad Ali Abdullah
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