Edit report at https://bugs.php.net/bug.php?id=53397&edit=1

 ID:                 53397
 Comment by:         cmbecker69 at gmx dot de
 Reported by:        mryaggi at hotmail dot com
 Summary:            Modulo is not accurate with double
 Status:             Verified
 Type:               Bug
 Package:            Scripting Engine problem
 Operating System:   All
 PHP Version:        Irrelevant
 Block user comment: N
 Private report:     N

 New Comment:

The operation a - (floor(a/b)*b) gives not the modulo, but the 
remainder.  Furthermore it seems the suggested patch does neither 
cater for large divisors nor large results.

It *might* be reasonable to stick with the current implementation,
and to state clearly in the documentation[1] that the modulus operator
gives correct results only for integers in the range
[-PHP_INT_MAX - 1, PHP_INT_MAX].  The current wording is somewhat
misleading, IMHO.

[1] <http://www.php.net/manual/en/language.operators.arithmetic.php>


Previous Comments:
------------------------------------------------------------------------
[2013-08-06 08:28:02] yohg...@php.net

Test with 5.5.1 32bit. This issue exists still.

------------------------------------------------------------------------
[2010-11-24 15:12:40] mryaggi at hotmail dot com

Description:
------------
In C++ :
1290594600000 % 86400000 = 37800000 //correct
But In PHP :
1290594600000 % 86400000 = 30811200 //wrong

However, in PHP : 
1290594600000 - (floor(1290594600000/86400000)*86400000) = 37800000 //correct!

Can modulo opertor be implemented this way when left value > PHP_INT_MAX ?

See Patch in attachement

Test script:
---------------
echo 1290594600000 % 86400000;
echo "\n";
echo 1290594600000 - (floor(1290594600000/86400000)*86400000);

Expected result:
----------------
37800000
37800000

Actual result:
--------------
30811200
37800000


------------------------------------------------------------------------



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