Re: [O] [PATCH] Add ob-J.el

2013-12-21 Thread Oleh
Hi Tom,

Yes, I'll write the documentation some time soon.

regards,
Oleh

On Fri, Dec 20, 2013 at 6:22 PM, Thomas S. Dye t...@tsdye.com wrote:
 Aloha Oleh,

 Oleh ohwoeo...@gmail.com writes:

 Hi all,

 Here's a patch to add babel support for J.
 I couldn't figure out how to make ob-J.elc a target for make,
 maybe someone can fix this.

 regards,
 Oleh


 Are you willing to draft documentation for ob-J.el? You can find a link
 for a documentation template here:

 http://orgmode.org/worg/org-contrib/babel/languages.html#develop

 I'm happy to proof-read and edit draft documentation, if you'd like.
 We're slowly catching up with the documentation for babel languages.

 Thanks for your contribution to Org mode!

 All the best,
 Tom

 --
 Thomas S. Dye
 http://www.tsdye.com



Re: [O] ox-bibtex: Allow for missing bibtex style

2013-12-21 Thread Julian Gehring

Hi Nicolas,


It sounds interesting. Would you want to provide a patch for that?


I would like to add this feature, if I knew how to program in lisp... 
Would you like to work on this together?  I could contribute on the side 
of documenting and testing, if this helps.


Best wishes
Julian




Re: [O] [PATCH] Add ob-J.el

2013-12-21 Thread Oleh
 Applied, Thanks!

 I've played with APL but never seriously, however I can see it being a
 perfect tool for manipulating Org-mode tables.

It's a nice tool, and I wrote this package just to learn J faster.

I wrote some time ago a package that takes a range, maps elisp code over it
and inserts it, e.g m4(* x x) becomes 0 1 4 9 16.
Then I realized that the parens and spaces weren't really necessary
and now this works as well: m4*xx.
After learning some of J, I see that even arguments aren't necessary,
e.g. m4*: describes the same thing in J.

If you want to try the package, it's called tiny in MELPA.
It's got one interesting application for org-mode: schedule/deadline
an activity for a span of days:

m0\n4|** TODO Something work-related %(1+ x)\nSCHEDULED: %(date mon
x) 10:00 +1w

expands to:

** TODO Something work-related 1
SCHEDULED: 2013-12-23 Mon 10:00 +1w
** TODO Something work-related 2
SCHEDULED: 2013-12-24 Tue 10:00 +1w
** TODO Something work-related 3
SCHEDULED: 2013-12-25 Wed 10:00 +1w
** TODO Something work-related 4
SCHEDULED: 2013-12-26 Thu 10:00 +1w
** TODO Something work-related 5
SCHEDULED: 2013-12-27 Fri 10:00 +1w

 If you have time to put some documentation up on Worg as a new [1]
 linked from [2] that'd be great.

I'll do this soon.

regards,
Oleh



Re: [O] [PATCH] Table continuation strings

2013-12-21 Thread Nicolas Goaziou
Hello,

Yasushi SHOJI ya...@atmark-techno.com writes:

 The thing I don't understand is the reason all Japanese entries have
 `:utf-8'. Would you kindly enlighten me the relationship among the
 followings:

  - transtion coding key (ie :utf-8, :default, :html)
  - your current buffer coding system
  - `buffer-file-coding-system' and friends

Coding keys are related to export back-ends. Therefore :latex entry will
be used for `latex' export, :html for `html' export, `:utf-8' for both
text (utf-8) and odt export, and so on.

As its name suggests, :default key is used as a fallback value when no
appropriate property is found. It makes up for a handy shortcut when
some strings are identical.

Coding system is a different thing. When `org-export-coding-system' is
non-nil, it will be used as the coding system for output (note that some
export back-ends override this behaviour). Otherwise, output will have
the same encoding as the source buffer.

 BTW, 前ページから続く should be 前ページからの続き

I applied your suggestion. Thank you.


Regards,

-- 
Nicolas Goaziou



Re: [O] Reading calendars in org mode: what is the best solution?

2013-12-21 Thread Alan Schmitt
Hi Stephen,

Stephen Eglen s.j.eg...@damtp.cam.ac.uk writes:

 On Thu, Dec 19 2013, Alan Schmitt wrote:

 I would like to have a read-only version of my calendars in my org
 agenda. These calendars (10 of them) currently live in Zimbra and
 iCould, and I am accessing them both using the native Calendar
 application on OS X and on my (Android) phone.

 I've looked at what the options are, and I can find two of them:
 - convert ics files into org files 
   (http://orgmode.org/worg/org-tutorials/org-google-sync.html)
 - set up a synchronization using caldav
   (https://github.com/dengste/org-caldav)

 Have you seen https://github.com/asoroa/ical2org.py
 I started using this about a week ago, and like it.  One strength
 compared to the worg entry is that it handles (some) recurring events.
 My approach is to download the .ics file and then run this python
 script.  

I had not seen this. I'll give it a try, thanks.

Alan



[O] org-mode mobile pull errors not marked FLAGGED

2013-12-21 Thread Trevor Alexander
According to the org-mode manual, there is a standard fast workflow for
handling errors in the mobile pull process, but my inbox org file
doesn't set provide the appropriate tags:

Pressing ? in that special agenda will display the full flagging note
in another window and also push it onto the kill ring. So you could use
? z C-y C-c C-c to store that flagging note as a normal note in the
entry. Pressing ? twice in succession will offer to remove the :FLAGGED:
tag along with the recorded flagging note (which is stored in a
property). In this way you indicate that the intended processing for
this flagged entry is finished.

If you are not able to process all flagged entries directly, you can
always return to this agenda view using C-c a ?.

Pressing those keystrokes doesn't do anything for me, since nothing is
marked :FLAGGED:. Here is a sample error block from my inbox org file:

* Body was changed in MobileOrg and on the computer F(edit:body)
[[olp:tracking.org:header1/header2][[2013-12-08 日 11:59]]]
** Old value
- Foo
** New value
- Bar


** End of edit

Is there some variable I need to change?

Thanks,
-Trevor



[O] auto-backing up your .emacs

2013-12-21 Thread Sharon Kimble

Can somebody help me please, I want to put this line into my .emacs -
'cp ~/.emacs ~/.emacs.d/.emacs-$(date +%Y%m%d-%R)' but it works as part
of a bash script, but I don’t know elisp to get it working in my .emacs.
What it does is save a dated and timed copy of your .emacs in your
~/.emacs.d so that when you're trying things out and learning how to
use .emacs you'll always have a backup copy. A case in point, last
night I had org2blog working, today, after fiddling its stopped
working, but if I'd had this operational I could just revert to a known
and working .emacs. So, can you help please?

Thanks
Sharon.
-- 
A taste of linux = http://www.sharons.org.uk
efever = http://www.efever.blogspot.com/
efever = http://sharon04.livejournal.com/
my git repo = https://bitbucket.org/boudiccas/dots
Debian testing, Fluxbox 1.3.5, LibreOffice 4.1.3.2
Registered Linux user 561944


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Description: PGP signature


Re: [O] auto-backing up your .emacs

2013-12-21 Thread Nathan DeGruchy
You should look into version control, like Git. It makes this process easy and 
integrates with Emacs with the Magit package. 

Nathan DeGruchy
nat...@degruchy.org

 On Dec 21, 2013, at 9:23 AM, Sharon Kimble boudic...@talktalk.net wrote:
 
 
 Can somebody help me please, I want to put this line into my .emacs -
 'cp ~/.emacs ~/.emacs.d/.emacs-$(date +%Y%m%d-%R)' but it works as part
 of a bash script, but I don’t know elisp to get it working in my .emacs.
 What it does is save a dated and timed copy of your .emacs in your
 ~/.emacs.d so that when you're trying things out and learning how to
 use .emacs you'll always have a backup copy. A case in point, last
 night I had org2blog working, today, after fiddling its stopped
 working, but if I'd had this operational I could just revert to a known
 and working .emacs. So, can you help please?
 
 Thanks
 Sharon.
 -- 
 A taste of linux = http://www.sharons.org.uk
 efever = http://www.efever.blogspot.com/
 efever = http://sharon04.livejournal.com/
 my git repo = https://bitbucket.org/boudiccas/dots
 Debian testing, Fluxbox 1.3.5, LibreOffice 4.1.3.2
 Registered Linux user 561944


Re: [O] ox-bibtex: Allow for missing bibtex style

2013-12-21 Thread Nicolas Goaziou
Hello,

Julian Gehring julian.gehr...@gmail.com writes:

 I would like to add this feature, if I knew how to program in lisp...
 Would you like to work on this together?  I could contribute on the
 side of documenting and testing, if this helps.

Fair enough. Here is a patch for you to test.


Regards,

-- 
Nicolas Goaziou
From 7f1ce8e8ba52152371e3aaf9af9a736fe443fde4 Mon Sep 17 00:00:00 2001
From: Nicolas Goaziou n.goaz...@gmail.com
Date: Sat, 21 Dec 2013 16:13:56 +0100
Subject: [PATCH] ox-bibtex: Allow nil style

* contrib/lisp/ox-bibtex.el (org-bibtex-process-bib-files,
  org-latex-keyword): Allow nil style.
---
 contrib/lisp/ox-bibtex.el | 21 +
 1 file changed, 13 insertions(+), 8 deletions(-)

diff --git a/contrib/lisp/ox-bibtex.el b/contrib/lisp/ox-bibtex.el
index 629695e..894d413 100644
--- a/contrib/lisp/ox-bibtex.el
+++ b/contrib/lisp/ox-bibtex.el
@@ -42,6 +42,8 @@
 ;;
 ;;   #+BIBLIOGRAPHY: foo plain option:-d
 ;;
+;; stylename can also be nil, in which case no style will be used.
+;;
 ;; Optional options are of the form:
 ;;
 ;;   option:-foobar pass '-foobar' to bibtex2html
@@ -184,13 +186,16 @@ Return new parse tree.
  (append (plist-get arguments :options)
 	 (list -citefile temp-file))
 	;; Call bibtex2html on specified file.
-	(unless (eq 0 (apply 'call-process
- (append '(bibtex2html nil nil nil)
-	 '(-a -nodoc -noheader -nofooter)
-	 (list --style
-	   (org-bibtex-get-style keyword))
-	 (plist-get arguments :options)
-	 (list (concat file .bib)
+	(unless (eq 0 (apply
+			   'call-process
+			   (append '(bibtex2html nil nil nil)
+   '(-a -nodoc -noheader -nofooter)
+   (let ((style
+	  (org-not-nil
+	   (org-bibtex-get-style keyword
+ (and style (list --style style)))
+   (plist-get arguments :options)
+   (list (concat file .bib)
 	  (error Executing bibtex2html failed))
 	(and temp-file (delete-file temp-file))
 	;; Open produced HTML file, and collect Bibtex key names
@@ -291,7 +296,7 @@ Fallback to `latex' back-end for other keywords.
 (if (not (equal (org-element-property :key keyword) BIBLIOGRAPHY))
 ad-do-it
   (let ((file (org-bibtex-get-file keyword))
-(style (org-bibtex-get-style keyword)))
+(style (org-not-nil (org-bibtex-get-style keyword
 (setq ad-return-value
   (when file
 (concat (and style (format \\bibliographystyle{%s}\n style))
-- 
1.8.5.2



Re: [O] auto-backing up your .emacs

2013-12-21 Thread Alexander Baier
You could look into the backup utilities that emacs provides out of the
box.  See the manual for further explanation: (info (Emacs) Backup).

On 2013-12-21 15:23 Sharon Kimble wrote:
 Can somebody help me please, I want to put this line into my .emacs -
 'cp ~/.emacs ~/.emacs.d/.emacs-$(date +%Y%m%d-%R)' but it works as part
 of a bash script, but I don’t know elisp to get it working in my .emacs.
 What it does is save a dated and timed copy of your .emacs in your
 ~/.emacs.d so that when you're trying things out and learning how to
 use .emacs you'll always have a backup copy. A case in point, last
 night I had org2blog working, today, after fiddling its stopped
 working, but if I'd had this operational I could just revert to a known
 and working .emacs. So, can you help please?

 Thanks
 Sharon.

HTH,
--
 Alexander Baier



Re: [O] [BUG] Add ob-J.el

2013-12-21 Thread Rick Frankel
On Fri, Dec 20, 2013 at 10:12:24AM -0700, Eric Schulte wrote:
 Applied, Thanks!
 
 I've played with APL but never seriously, however I can see it being a
 perfect tool for manipulating Org-mode tables.
 
 If you have time to put some documentation up on Worg as a new [1]
 linked from [2] that'd be great.
 
 I added ob-J to the org-babel-load-languages customization variable and
 it is now compiling with make.

The org-mode build and install now fails for me due to the fact that
ob-J requires j-console, which seems to be part of the package
'j-mode', and is not part of the standard emacs.

Perhaps this should be in contrib, unless the depency on j-console can
be factored out.

rick



Re: [O] auto-backing up your .emacs

2013-12-21 Thread Thierry Banel
Sharon Kimble boudiccas at talktalk.net writes:

 
 Can somebody help me please, I want to put this line into my .emacs -
 'cp ~/.emacs ~/.emacs.d/.emacs-$(date +%Y%m%d-%R)' but it works as part
 of a bash script, but I don’t know elisp to get it working in my .emacs.
 What it does is save a dated and timed copy of your .emacs in your
 ~/.emacs.d so that when you're trying things out and learning how to
 use .emacs you'll always have a backup copy. A case in point, last
 night I had org2blog working, today, after fiddling its stopped
 working, but if I'd had this operational I could just revert to a known
 and working .emacs. So, can you help please?
 
 Thanks
 Sharon.

Hi Sharon

Emacs already have a builtin file version control.
If you use Emacs itself to edit your .emacs,
it will most likely create a .emacs~, which is a backup.
This is controlled by the variable make-backup-files.
Add this line to your .emacs:
  (setq make-backup-files t)

You may want to have several backup files.
They will be numbered with names like .emacs.~7~
Then add this line to your .emacs:
  (setq version-control t)

Of course this works for all files visited by Emacs, not only .emacs.

Look at the documentation:
  within Emacs, type C-h i
  then navigate to
Emacs  Files  Saving  Backup 

Have fun






Re: [O] auto-backing up your .emacs

2013-12-21 Thread Sharon Kimble
On Sat, 21 Dec 2013 16:16:20 + (UTC)
Thierry Banel tbanelweb...@free.fr wrote:

 Sharon Kimble boudiccas at talktalk.net writes:
 
  
  Can somebody help me please, I want to put this line into my .emacs
  - 'cp ~/.emacs ~/.emacs.d/.emacs-$(date +%Y%m%d-%R)' but it works
  as part of a bash script, but I don’t know elisp to get it working
  in my .emacs. What it does is save a dated and timed copy of
  your .emacs in your ~/.emacs.d so that when you're trying things
  out and learning how to use .emacs you'll always have a backup
  copy. A case in point, last night I had org2blog working, today,
  after fiddling its stopped working, but if I'd had this operational
  I could just revert to a known and working .emacs. So, can you help
  please?
  
  Thanks
  Sharon.
 
 Hi Sharon
 
 Emacs already have a builtin file version control.
 If you use Emacs itself to edit your .emacs,
 it will most likely create a .emacs~, which is a backup.
 This is controlled by the variable make-backup-files.
 Add this line to your .emacs:
   (setq make-backup-files t)
 
 You may want to have several backup files.
 They will be numbered with names like .emacs.~7~
 Then add this line to your .emacs:
   (setq version-control t)
 
 Of course this works for all files visited by Emacs, not only .emacs.
 
 Look at the documentation:
   within Emacs, type C-h i
   then navigate to
 Emacs  Files  Saving  Backup 
 
Thanks for this. I called up the package menu and found
'backup-each-save' so I've installed that to try out. Hopefully it will
work okay, but time will tell :)

Sharon.
-- 
A taste of linux = http://www.sharons.org.uk
efever = http://www.efever.blogspot.com/
efever = http://sharon04.livejournal.com/
my git repo = https://bitbucket.org/boudiccas/dots
Debian testing, Fluxbox 1.3.5, LibreOffice 4.1.3.2
Registered Linux user 561944


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Description: PGP signature


[O] split ascii-plot package into pure ascii unicode

2013-12-21 Thread Thierry Banel
I removed unicodes characters from the orgtbl-ascii-plot package.
This makes it safe for Org exporters.
The unicode version is kept separatly, as an extension example.

The file (code  doc) is here
http://orgmode.org/worg/org-contrib/orgtbl-ascii-plot.html

| values | ascii plot   |
|+--|
| 25 | WW.  |
| 16 | WWWH |
|  9 | WW:  |
|  4 | H|
|  1 | :|
|  0 |  |
|  1 | :|
|  4 | H|
|  9 | WW:  |
| 16 | WWWH |
| 25 | WW.  |
| 36 | V|
| 49 |  |
#+TBLFM: $2='(orgtbl-ascii-draw $1 0 49 12)

By the way, the FSF acknowleged my copyright assignment
(the whole process took 3 weeks for me).

Have fun
Thierry





[O] Org-mac-link misplaced quotes?

2013-12-21 Thread Alexander Poslavsky
I regularly use org-mac-link from contrib/. It works fine, but somehow my
links are a bit mangled, I get:

[[http://orgmode.org/worg/org-contribute.html#sec-4][How to contribute to
Org?]]

Instead of:

[[http://orgmode.org/worg/org-contribute.html#sec-4][How to contribute to
Org?]]

(Notice the quotation-marks, it's how applescript returns the string)

This small patch fixes that. I hope the patch is done correctly.


0001-org-as-mac-chrome-get-frontmost-url-fix-to-remove-un.patch
Description: Binary data


Re: [O] [BUG] Add ob-J.el

2013-12-21 Thread Oleh
 I added ob-J to the org-babel-load-languages customization variable and
 it is now compiling with make.

 The org-mode build and install now fails for me due to the fact that
 ob-J requires j-console, which seems to be part of the package
 'j-mode', and is not part of the standard emacs.

 Perhaps this should be in contrib, unless the depency on j-console can
 be factored out.


Hi Rick,

j-console is required currently for :session eval only. Regular eval
works without it.
You can remove the top level (require 'j-console) now if you want, or I can
remove it a bit later when I get push access.
The top level one isn't needed since it's required again in *-initiate-session.

The actual dependency on j-console to do the work isn't that different
from when other org-babel implementations depend on nrepl or inf-ruby.
But as it's just a simple comint interaction, I could eventually
remove this dependency.

regards,
Oleh



Re: [O] [BUG] Add ob-J.el

2013-12-21 Thread Eric Schulte
Oleh ohwoeo...@gmail.com writes:

 I added ob-J to the org-babel-load-languages customization variable and
 it is now compiling with make.

 The org-mode build and install now fails for me due to the fact that
 ob-J requires j-console, which seems to be part of the package
 'j-mode', and is not part of the standard emacs.

 Perhaps this should be in contrib, unless the depency on j-console can
 be factored out.


 Hi Rick,

 j-console is required currently for :session eval only. Regular eval
 works without it.
 You can remove the top level (require 'j-console) now if you want, or I can
 remove it a bit later when I get push access.
 The top level one isn't needed since it's required again in 
 *-initiate-session.

 The actual dependency on j-console to do the work isn't that different
 from when other org-babel implementations depend on nrepl or inf-ruby.
 But as it's just a simple comint interaction, I could eventually
 remove this dependency.

 regards,
 Oleh


I just removed the top-level require, thanks for reporting.

-- 
Eric Schulte
https://cs.unm.edu/~eschulte
PGP: 0x614CA05D



Re: [O] [PATCH] Table continuation strings

2013-12-21 Thread Yasushi SHOJI
HI,

At Sat, 21 Dec 2013 10:05:35 +0100,
Nicolas Goaziou wrote:
 
 Yasushi SHOJI ya...@atmark-techno.com writes:
 
  The thing I don't understand is the reason all Japanese entries have
  `:utf-8'. Would you kindly enlighten me the relationship among the
  followings:
 
   - transtion coding key (ie :utf-8, :default, :html)
   - your current buffer coding system
   - `buffer-file-coding-system' and friends
 
 Coding keys are related to export back-ends. Therefore :latex entry will
 be used for `latex' export, :html for `html' export, `:utf-8' for both
 text (utf-8) and odt export, and so on.
 
 As its name suggests, :default key is used as a fallback value when no
 appropriate property is found. It makes up for a handy shortcut when
 some strings are identical.

Ah, OK.  Those coding keys are for the back-ends to select proper
strings, not for the string encoding.

Then, is there any restriction with HTML back-ends? Why does it need
numeric character reference instead of just plain characters, if the
coding system is not a concern?

 Coding system is a different thing. When `org-export-coding-system' is
 non-nil, it will be used as the coding system for output (note that some
 export back-ends override this behaviour). Otherwise, output will have
 the same encoding as the source buffer.

Correct me if I'm wrong.  My understainding is as follows: All
translation strings is in `emacs-internal' coding system, since it is
defined in .el.  A org file ready to be exported has a coding system
specific to the buffer, ie. utf-8, iso-latin-1, euc-jp, etc.

Org export back-ends get a strings for the back-ends from the
translation table when appropriate.  At that time Emacs converts the
strings encoding system to match the buffer encoding system (or does
Emacs convert all encoding when it writes to file?).  Back-ends uses
`org-export-coding-system' if set, otherwise use the current buffer
coding system.


If my understanding is ok, all entries of Japanese translation should
have :default instead of :utf-8.

Thanks,
-- 
yashi





[O] longer agenda in mobile org

2013-12-21 Thread Joseph A. Cua
By default, org-mobile-push seems to put only the current week's agenda
into agendas.org. Is this configurable? I'd like to see agendas for the
next several weeks or months in mobileOrg.


[O] Get the maximum date within a list of dates

2013-12-21 Thread Truong Ha
Hi,
How can I get the maximum date within rows of dates in the table?
|Amount | Date |+---+--+|   158 | 
2013-12-01 Sun ||   148 | 2013-12-02 Mon ||   105 | 2013-12-03 
Tue ||   421 | 2013-12-08 Sun ||40 | 2013-12-10 Tue ||   
125 | 2013-12-11 Wed ||50 | 2013-12-12 Thu ||83 | 
2013-12-13 Fri ||   116 | 2013-12-14 Sat ||55 | 2013-12-15 
Sun ||90 | 2013-12-16 Mon ||   187 | 2013-12-17 Tue ||
96 | 2013-12-18 Wed ||86 | 2013-12-19 Thu ||90 | 
2013-12-20 Fri ||   135 | 2013-12-21 Sat ||23 | 2013-12-22 
Sun |
Thanks,Ha 

Re: [O] Get the maximum date within a list of dates

2013-12-21 Thread Bastien
Hi Truong,

Truong Ha truonghat...@outlook.com writes:

 How can I get the maximum date within rows of dates in the table?

 |Amount | Date |
 +---+--+
 |   158 | 2013-12-01 Sun |
 |   148 | 2013-12-02 Mon |
 |   105 | 2013-12-03 Tue |
 |   421 | 2013-12-08 Sun |
 |40 | 2013-12-10 Tue |
 |   125 | 2013-12-11 Wed |
 |50 | 2013-12-12 Thu |
 |83 | 2013-12-13 Fri |
 |   116 | 2013-12-14 Sat |
 |55 | 2013-12-15 Sun |
 |90 | 2013-12-16 Mon |
 |   187 | 2013-12-17 Tue |
 |96 | 2013-12-18 Wed |
 |86 | 2013-12-19 Thu |
 |90 | 2013-12-20 Fri |
 |   135 | 2013-12-21 Sat |
 |23 | 2013-12-22 Sun |

Put your cursor in @2$2 then C-c ^ T to sort by reversed date
(oldest last).

HTH,

-- 
 Bastien



Re: [O] longer agenda in mobile org

2013-12-21 Thread Bastien
Joseph A. Cua ja...@cornell.edu writes:

 By default, org-mobile-push seems to put only the current week's
 agenda into agendas.org. Is this configurable? I'd like to see
 agendas for the next several weeks or months in mobileOrg.

See `org-agenda-span' and custom agendas in general.

-- 
 Bastien



Re: [O] split ascii-plot package into pure ascii unicode

2013-12-21 Thread Bastien
Hi Thierry,

Thierry Banel tbanelweb...@free.fr writes:

 I removed unicodes characters from the orgtbl-ascii-plot package.
 This makes it safe for Org exporters.
 The unicode version is kept separatly, as an extension example.

Thanks for taking care of this.

 By the way, the FSF acknowleged my copyright assignment
 (the whole process took 3 weeks for me).

Well, that's not too bad, it can take very much longer.

Have a good day!

-- 
 Bastien



Re: [O] Get the maximum date within a list of dates

2013-12-21 Thread Bastien
Bastien b...@gnu.org writes:

 Put your cursor in @2$2 then C-c ^ T to sort by reversed date
 (oldest last).

Also remember you can use ELisp in formulas:

| Date 1  | Date 2  | Duration |
|-+-+--|
| [2013-12-21 sam. 00:00] | [2013-12-22 dim. 00:00] |  86400.0 |
#+TBLFM: $3='(- (org-time-string-to-seconds $2) (org-time-string-to-seconds 
$1));L

PS: note the quotes around $2 and $1, they are necessary so
that the date is not literally inserted in the formulas when Org
is computing it.

HTH,

-- 
 Bastien