Date in Julian Format

[Marcelo De Florio]

Hown can i obtain the date in julian format ?

[Bill McNAMARA_1]

there are lots of args you can give to the date command to print out the date in a number of formats, text mm/dd/yy, dd/mm/yy, dd/month/yy..
but I have no idea what or who Julian is?
You may want to look at your locale settings.
Type in locale, and man locale and date for more.

Later,
Bill

[John Poff · Accepted solution]

If you like it in the format of YYDDD, try:

date +'%y%j'

If you prefer MMMMDDD, try:

date +'%Y%j'

[James R. Ferguson]

Hi:

# date +%y%j

...returns 01152...

# date +%Y%j

...returns 2001152

...JRF...

[MANOJ SRIVASTAVA]

Hi Marcelo

use

date='date+%m+%d'

Manoj Srivastava

[A. Clay Stephenson]

Hi Marcelo,

No guys, it's obvious that none of you are physicists or astronomer's (and possibly I'm both though one on a amateur basis) Julian dates are floating point number of days since approximately 0000hrs UCT Jan 1, 4712 B.C.E.
The fractional part represents the fractional part of the day to whatever precision.

Given that, Marcelo, yes, I've got routines to do this but I suspect that you want TRUNCATED julian dates (integer representations).

I suppose you want integer routines to convert year,month, and day to integer Julian equivalent (and possibly the inverse). If that's what you are looking for, let me know and I'll dig them up. It seems to me I coded the trucated versions in awk embedded in a shell script.

Regards, Clay

[James R. Ferguson]

Hello Clay:

On the contrary, I am aware of the nuance. I believe that there are some good articles from the US Naval Observatory sites on this. For some history, readers can take a look at this:

http://www.faqs.org/faqs/astronomy/faq/part3/section-6.html

For general, commercial computing, I have always seen "Julian" infer the notation of YYDDD.

With my regards!

...JRF...

[A. Clay Stephenson]

Hi James,

I suppose I'm too much of a purist to allow that; it's sort of like football coaches talking about momentum.

Regards, Clay

[James R. Ferguson]

Hi Clay:

Well put. I'm a big fan of Heisenberg, too. ;-)

Regards!

...JRF...

[CHRIS_ANORUO]

Hi Caesar's Senator,

Try DATE=`date +%A,%d:%m:%Y`

I know why you want this in Julian - Senator