calculate time from seconds, day of year, and year

[Dave_Thomson]

I've got a data file where they saved three columns, seconds since midnight, day of year, and year.  I'm trying to create a LabVIEW timestamp from these three numbers.  From seconds since midnight, I can create sec, minutes, and hours.  If I feed these into a time cluster with Day of Year and Year, the output timestamp is 0.  Doesn't work.  Although it has a Day of Year input element, apparently the Date/Time to Seconds function requires day of month and month to work.

The only obvious solution I can imagine at this point is to calculate month and day from day of year, which would involve a month lookup table and a leap year check.

Any clever solutions I'm missing?

DaveT

[tbob]

The day of week and day of year can be 0 and it will still work.  But the month and day of month are required.  I guess you would have to look up the month and day from day of year with a leap year check.

[Dennis_Knutson · Accepted solution]

Dave,

I found a Julian to Georgian date here.

[Dave_Thomson]

Thanks, Dennis!  I did do a search, but didn't find that.  I was hoping there was an easy trick like that.

Cheers,

   DaveT

[Mattjk]

I have another way, the DBL conversion VI converts time to a "numeric value" that started counting since the year 1901.  Now you can do some math in a seperate VI to determin how many "numeric values" is 1 year, 1 day, 1 second.  Then do your math to add up all "numeric values" and then convert your DBL to timestamp again.

[altenbach]

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@Mattjk wrote:

I have another way, the DBL conversion VI converts time to a "numeric value" that started counting since the year 1901.  Now you can do some math in a seperate VI to determin how many "numeric values" is 1 year, 1 day, 1 second.  Then do your math to add up all "numeric values" and then convert your DBL to timestamp again.

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This can get a bit complicated, for example make sure you take care of leap years and such.

[Mattjk]

You don't need to worry about a leap year doing it this way.

Example:

Seconds since midnight: say 60

Day of year: say 222 (60seconds x 60 minutes x 24 hours) X 222= 19180800

Year: say 2014 (Jan. 1st 2014 at exactly 12:00am) (using code) = 3471397200

Each year after = 31536000

So just add all the numbers together and use the number to timestamp VI in the timing pallet to convert back to a date.

There is a little bit of work with the year because you can't assume that

Year 1900 to 2014 is 114 years which is

114 X 31536000

First calcualte an offset value from December 31st 1903 at 7pm to any year that starts with Jan.1st at 12am.

Then add Years after (multiplied by 31536000)