Shoutbox

I'm coding this program in Java and I absolutely need a formula to be able to calculte the numbers of days lived.

I searched the net, I couldn't find much.

What I came up with is this :

[ {365 * (currentyear -yearborn)} + {(currentyear -yearborn) / 4} ] - [(daysofyearthatpassed*) + (dayborn)] + [(daysofyearthatpassed*)+(currentday)]


daysofyearthatpassed* : depending on which month and if the year has 366 or 365 days, I calculated an amount that I just add to the day.



As you can see this isn't working.. So if you guys find a better way or can actually correct this, please don't be shy to do so.

couldn't you just use something like:
Date today = new Date();
Date birth =new Date(.....);

and subtract them? although the date object sucks in java...
and semi-replaced by Calender... maybe the api is more helpfull...

No... cause you'd need to add in leap years and such.

quote:

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Originally posted by alby
I searched the net, I couldn't find much.

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I searched the net and found tons

search with "Java Datediff"

http://forum.java.sun.com/thread.jspa?threadID=48...&messageID=2292012
http://forum.java.sun.com/thread.jspa?forumID=31&threadID=395202
http://www.java2s.com/Code/Java/Development-Class...etweentwodates.htm
http://jalbum.net/api/se/datadosen/util/Dates.html
http://www.rupertjones.com/dateutil/docs/api/com/...util/DateDiff.html
etc

quote:

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Originally posted by UTI
No... cause you'd need to add in leap years and such.

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I dunno exactly for Java, but in any other language I know Date objects are in milliseconds or at least in seconds or another form which you can substract from each other.

You do not need to take in account leap years, lead days and leap seconds. This is automatically done as the calenders of the objects use Gregorian calenders.

But as said, I dunno if this is also the case in Java (but I would be surprised if it wasn't)...

quote:

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Originally posted by CookieRevised
I dunno if this is also the case in Java

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The Java Date object (and anything to do with dates) uses the Gregorian calendar, and will correctly deal with leap years.

this is why dates need to go metric...

quote:

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Originally posted by fluffy_lobster
this is why dates need to go metric...

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They'll never go metric, simply because it's not possible to define a metric system for dates that everyone understands. Look at Swatch's failed .beat system for instance.

quote:

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Originally posted by fluffy_lobster
this is why dates need to go metric...

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Yep, well, we need a decimal calendar (metric means based on the metre). Problem is, days and years are both determined by Earth's movement. You can't make up an arbitary unit like the metre, a year has 365 days (and a bit), that's just the way it is.

just use the counter psm script or the holiday counter have a look at how they did it