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Converting dates from the Persian calendar to Gregorian

2 messages · BXC (Bendix Carstensen), Peter Dalgaard

#
-----Original Message-----
From: Amy Mikhail [mailto:amy.mikhail at googlemail.com] 
Sent: 7. januar 2009 14:33
To: BXC (Bendix Carstensen)
Subject: Re: [R-sig-Epi] Converting dates from the Persian calendar to Gregorian

Hi Bendix,

Thanks - had not heard of Emacs before although just looking at it briefly it seems to be more of a text editor than a database type program, also although it converts from gregorian to other calendars, I'm not sure if it converts in the opposite direction.

I'll post this to R-devel and see if there are any takers.

Best wishes,
Amy
On Wed, Jan 7, 2009 at 1:00 PM, BXC (Bendix Carstensen) <bxc at steno.dk> wrote:
I already sent this request off to inquire with Peter Dalgard and Martyn Plummer from the R-core team, and got this back from Peter:
	

	> -----Original Message-----
	> From: Peter Dalgaard [mailto:P.Dalgaard at biostat.ku.dk]
	> Sent: 7. januar 2009 13:43
	> To: BXC (Bendix Carstensen)
	> Cc: pd at biostat.ku.dk; Martyn Plummer
	> Subject: Re: FW: [R-sig-Epi] Converting dates from the
	> Persian calendar to Gregorian
	>
	
	> Also notice that M-x calendar in Emacs does a lot of this stuff.
	>
	>
	> p o           calendar-print-other-dates
	> p m           calendar-print-mayan-date
	> p f           calendar-print-french-date
	> p i           calendar-print-islamic-date
	> p h           calendar-print-hebrew-date
	> p a           calendar-print-astro-day-number
	> p j           calendar-print-julian-date
	> p c           calendar-print-iso-date
	> p p           calendar-print-persian-date
	> p e           calendar-print-ethiopic-date
	> p k           calendar-print-coptic-date
	> p C           calendar-print-chinese-date
	> p d           calendar-print-day-of-year
	>
	
	Yes it might be a good idea to pose this to the R-devel list as a facility that should be included in R --- presumably with the same facilities as in emacs.
	

	Best regards,
	Bendix
	
	> -----Original Message-----
	
	> From: Amy Mikhail [mailto:amy.mikhail at googlemail.com]
	> Sent: 7. januar 2009 13:45
	> To: BXC (Bendix Carstensen)
	> Cc: r-sig-epi at stat.math.ethz.ch
	> Subject: Re: [R-sig-Epi] Converting dates from the Persian
	> calendar to Gregorian
	>
	> Hi Bendix,
	>
	> Many thanks - yes, I had already visited Homam's page.  I
	> have posted a message there asking if there is some way to
	> link his code / function to my MS Access database, but having
	> this as a function in R would be better.
	>
	> Any takers, who know both C and R?  Should I also post this
	> to the R devel list?
	>
	> Best wishes,
	> Amy
	>
	>
	>
	> On Wed, Jan 7, 2009 at 12:26 PM, BXC (Bendix Carstensen)
> <bxc at steno.dk> wrote:
>
	>
	>       Hi Amy,
	>       you probaly already have visited:
	>       http://www.codeproject.com/KB/cs/JalaliCalendar.aspx
	>       where the Iranian guy Homam Hosseini provides a
	> discussion of the conversion, and some C code to do it.
	>
	>       I am a C ignorant, but surely someone in the
	> R-community would be able to take this code (and in
	> collaboration with Homam) provide a function that converts
	> Iranian / Jalali dataes to and from the Gregorian Date class??
	>
	>       Best regards
	>       Bendix
	>
	>
	>       > -----Original Message-----
	>       > From: r-sig-epi-bounces at stat.math.ethz.ch
	>       > [mailto:r-sig-epi-bounces at stat.math.ethz.ch] On
	> Behalf Of Amy Mikhail
	>       > Sent: 7. januar 2009 12:40
	>       > To: r-sig-epi at stat.math.ethz.ch
	>       > Subject: [R-sig-Epi] Converting dates from the Persian
	>       > calendar to Gregorian
	>       >
	>       > Dear Epi list,
	>       >
	>       > This is not a strictly epidemiological question, but an issue
	>       > that anyone might face if presented with a dataset containing
	>       > dates in a non-gregorian format.
	>       >
	>       > I am currently developing a database (in MS Access) for a
	>       > public health study, the results of which I intend to analyse
	>       > in R.  I have a small problem, in that the date each patient
	>       > visits the clinic will be entered into the database in the
	>       > Persian  / Jalali calendar format - e.g. today's
	>       > date in the Persian calendar is 18.10.1387.   For the
	>       > analysis however I
	>       > need these dates to be converted to Gregorian, so that I can
	>       > have months on the x axis of plots, etc.
	>       >
	>       > Does anyone know of a function / some code already written
	>       > that could do this conversion in R?  It is much too complex
	>       > for me to figure out (since the Persian new year starts on
	>       > 21st March, and although there are also 12 months they have
	>       > different lengths to gregorian months).  I'm guessing it
	>       > would require loops and such but this is beyond my current
	>       > level of R knowledge.
	>       >
	>       > I have found some online tools that do the conversion of
	>       > individual dates, but there seems to be nothing out there
	>       > that would convert a whole dataset's worth of dates.
	>       >
	>       > Any suggestions much appreciated,
	>       > With best wishes,
	>       > Amy
	>       >
	>       >
	>       > --
	>       > Amy Mikhail
	>       > Program Manager, ACTc Afghanistan Malaria Project London
	>       > School of Hygiene & Tropical Medicine HPRO, Charahi-e-Shahid,
	>       > Shar-e-Naw, Kabul, Afghanistan
	>       >
	>       > Email (Afg): amy.mikhail at googlemail.com
	>       > Email (UK): Amy.Mikhail at lshtm.ac.uk
	>       > Tel (Afg): +93 (0)706 126627
	>       > Tel (UK): +44 (0)781 4176107
	>       >
	>
	>       >       [[alternative HTML version deleted]]
	>       >
	>       > _______________________________________________
	>       > R-sig-Epi at stat.math.ethz.ch mailing list
	>       > https://stat.ethz.ch/mailman/listinfo/r-sig-epi
	>       >
	>
	>
	>
	>
	> --
	> Amy Mikhail
	> Program Manager, ACTc Afghanistan Malaria Project London
	> School of Hygiene & Tropical Medicine HPRO, Charahi-e-Shahid,
	> Shar-e-Naw, Kabul, Afghanistan
	>
	> Email (Afg): amy.mikhail at googlemail.com
	> Email (UK): Amy.Mikhail at lshtm.ac.uk
	> Tel (Afg): +93 (0)706 126627
	> Tel (UK): +44 (0)781 4176107
	>
	> 




--
Amy Mikhail
Program Manager, ACTc Afghanistan Malaria Project London School of Hygiene & Tropical Medicine HPRO, Charahi-e-Shahid, Shar-e-Naw, Kabul, Afghanistan

Email (Afg): amy.mikhail at googlemail.com
Email (UK): Amy.Mikhail at lshtm.ac.uk
Tel (Afg): +93 (0)706 126627
Tel (UK): +44 (0)781 4176107
#
BXC (Bendix Carstensen) wrote:
briefly it seems to be more of a text editor than a database type
program, also although it converts from gregorian to other calendars,
I'm not sure if it converts in the opposite direction.

Emacs does many things...

The opposite direction is "g p" calendar-goto-persian-date.

See also

http://emr.cs.iit.edu/~reingold/calendars.shtml

with links to the conversion codes in Common LISP and C++