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Julian date from calender date

is there any simple command in ksh (not big programme) from which I can obtain julian date from calender date of format YYYY-MM-DD

Does this work for you?

Code:

date -d '2007-04-01' +'%Y %j'

(Guess what the %j means!)

The first two results look promising.

-- Well, the idea remains. ;)

sorry removed the post... would like to do some homework prior to that.

Quote:

Originally Posted by wjevans_7d1@yahoo.co (Post 2827343)

Does this work for you?

Code:

date -d '2007-04-01' +'%Y %j'

(Guess what the %j means!)

On my system, "%j" gets you the day of the year. GNU "date" version 5.97
"man -k julian" returns nothing

The above command is wroking on linux but not on unix. I am trying to go through the manual pages for 'date' command, so far unable to get the same result on unix system.

Quote:

Originally Posted by tostay2003 (Post 2860881)

The above command is wroking on linux but not on unix. I am trying to go through the manual pages for 'date' command, so far unable to get the same result on unix system.

Not on my Linux!!! (PCLOS 2007)
My output:

Code:

[mherring@localhost ~]$ date -d '2007-04-01' +'%Y %j'

2007 091

I want the same output which you are getting. the year and the number of days.

Hi.

The accepted and precise meanings of the term may be a sub-issue here.

Quote:

The use of Julian date to refer to the day-of-year (ordinal date) is usually considered to be incorrect, however it is widely used that way in the earth sciences and computer programming.

-- more at http://en.wikipedia.org/wiki/Julian_date

cheers, makyo

Not able to figure out how do get it on Unix system.
equivalent of following command in linux

Code:

date -d '2007-04-01' +'%Y %j'

Quote:

Originally Posted by tostay2003 (Post 2860919)

Not able to figure out how do get it on Unix system.
equivalent of following command in linux

Code:

date -d '2007-04-01' +'%Y %j'

Does your Unix system have the date command at all? If so, then "man date" If not, can you do "man -k date" to see what the command is?

Google any help?

date command exists on unix server. Not able to figure out, how to convert into julian date.

Trying google as well, so far no luck, may be soon. :(

Hi.

There is a perl version of date at: http://search.cpan.org/src/CWEST/ppt...ate/index.html -- the perl Power Tools collection.

Running it to get what some call the Julian date produces:

Code:

% ./date.jgross "+%j"

228

Best wishes ... cheers, makyo

Need it through ksh or bash.

Hi.

Ah.

There is a collection of cfaj's scripts at http://members.torfree.net/chris/books/cfaj/ssr.html

In Chapter 8 he has a number of functions for date manipulation. Some appear to deal with "Julian". I have not tried them.

There are several algorithms in pseudo-code that IBM published just before Y2K. I have listed the contents below. If you really cannot find anything else, I can post the algorithms. IBM seems to have archived them -- I cannot find them on their web page http://www.software.ibm.com/year2000/tips15.html -- perhaps you would have better luck than I did -- or perhaps you can Google for them. You would need to translate those into shell scripts. I did a few in perl just to check them out.

Finally, sourceforge has a number of codes for Julian, but they appear to be the real Julian date forms.

Best wishes ... cheers, makyo

Quote:

Date Calculation Algorithms

These algorithms should be implemented using 32 bit or 9 digit
precision arithmetic in the computer language of your choice. All
division is integer division, i.e. you drop the remainder. For
example, 35 / 4 is 8; to make this clear the algorithms use the INT
function, INT(35/4). These algorithms make use of the MOD function,
the remainder after integer division.

The following algorithms are included:

* Convert from YYYY,MM,DD to YYYY,NNN and determine day-of-week
* Convert from YYYY,NNN to YYYY,MM,DD and determine day-of-week
* Convert from YYYY,NNN to Lilian (day 1=Fri Oct 15, 1582)
* Convert from Lilian to YYYY,NNN
* Convert from Lilian to day-of-week
* Convert from YYYY,MM,DD to YYYY,NNN
* Convert from YYYY,MM,DD to day-of-week

NOTE: Day 1 of the Lilian date in these algorithms is Friday, 15
October 1582.