Bug #54396 [Opn->Nab]: Php appears to be one day off with Julian Day count

Edit report at https://bugs.php.net/bug.php?id=54396&edit=1 ID: 54396 Updated by: heiglandreas@php.net Reported by: satovey at yahoo dot com Summary: Php appears to be one day off with Julian Day count -Status: Open +Status: Not a bug Type: Bug Package: Date/time related Operating System: Win7 PHP Version: 5.3SVN-2011-03-26 (SVN) Block user comment: N Private report: N New Comment: The jdtogregorian function expects an integer as parameter. You are passing a float which is converted to int via floor. Therefore the date is not what you expect it to be. Have a look at http://php.net/manual/en/function.jdtogregorian.php#43470 for an explanation how to get the value you expected. Previous Comments: ------------------------------------------------------------------------ [2011-03-26 18:02:28] satovey at yahoo dot com Description: ------------ I am using Xamp on Windows 7 x64 in case that is relevant. The following two sites: http://www.fourmilab.ch/documents/calendar/ http://quasar.as.utexas.edu/BillInfo/JulianDateCalc.html are in agreement. They produce a Julian Day count of 2455646.5 for 3/26/2011. However, PHP's jdtogregorian() functions produces the following: 2455646.5 => 3/25/2011 || 2455647.5 => 3/26/2011 Test script: --------------- $julianDayCntI = 2455646.5; $julianDayCntII = 2455647.5; $gregDateI = jdtogregorian($julianDayCntI); $gregDateII = jdtogregorian($julianDayCntII); echo "$julianDayCntI => $gregDateI || $julianDayCntII => $gregDateII <br />"; Expected result: ---------------- I do not have the mathematical skills to fix this bug, so I will leave correcting this bug it up to those who are more mathematically astute. ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=54396&edit=1