Getting current julian date

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Level 1

8 points

Getting current julian date

Hi People,

Does anyone know how i go about getting the current julian date? or is it just one of those things i have to calculate myself.

Thanks.

N.

Macbook Pro, Mac OS X (10.5.5)

Posted on Oct 24, 2008 2:40 AM

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Answer 1

Apple Munky Author

Level 1

8 points

Oct 24, 2008 3:57 AM in response to SexyAndOhSoWitty

Yeah i've looked at that unfortunatly the only calendars which appear to have support are:

NSGregorianCalendar
NSBuddhistCalendar
NSChineseCalendar
NSHebrewCalendar
NSIslamicCalendar
NSIslamicCivilCalendar
NSJapaneseCalendar

which are locale based. I could work it out from a unixtime value but i'm sure that would introduce some rounding errors. Would just think that it would be included.

Message was edited by: Apple Munky

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Answer 2

Apple Munky Author

Level 1

8 points

Oct 25, 2008 4:13 PM in response to Apple Munky

I guess actually thinking about it, the calculation isn't that tricky 🙂 Always looking for the complicated solution when the simple on is right in front of you 🙂

To calculate the current julian date: (unixtime/86400)+2440587.5

Which is convert the unixtime to days and then add the number of (julian)days which have elapsed between 4713 BC January 1 (when the julian calendar began) and Jan 1st 1970 (when unixtime began)

Simple when you work it out.

N.

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Answer 3

Oct 24, 2008 3:37 AM in response to Apple Munky

Hi, i'm not quite sure what youre asking for but did you tried this:


NSDate *today = [NSDate date];

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Answer 4

Oct 24, 2008 3:48 AM in response to Apple Munky

Check out the Date and Time Programming Guide for Cocoa page 16 "Converting from One Calendar to Another".

[https://developer.apple.com/iphone/library/navigation/AllResources.html]

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