Re: org table calc and lisp for hh:mm timetable

[Christian Moe <mail@christianmoe.com>]

Hi,

Returning to this thread:

1. I love Eric's macro wrapper idea -- now time arithmetic in tables 
gets truly manageable. If it's not included into Org-mode, it's a must 
for Worg!

2. There's duplication with org-timer-hms-to-secs and 
org-timer-secs-to-hms. (Cf. my 
http://permalink.gmane.org/gmane.emacs.orgmode/39501.)

Do Martin's/Bastien's/Eric's hms/seconds conversion functions add 
value that should be patched into org-timer?

3. One thing Eric's converters do and org-timer doesn't is to handle a 
string with only two two-digit groups (e.g. 12:45).

Eric's converters interpret it as 12m 45s -- good for running times. 
The functions I posted (see link above) interpreted such strings as 
12h 45m -- good for time of day.

I suggest the latter is more convenient for most use cases: When I'm 
working with seconds (running times, audio track durations) it's sort 
of a technical use, so I'm prepared to add 0 hours in front. When a 
time of day like 12:45 is good enough, I don't want to have to add 00 
seconds in back. (And am/pm is not used in my locale.)

Yours,
Christian

On 3/20/11 6:50 PM, Eric Schulte wrote:
> I wrapped Bastien's functions below in a simple macro, which IMO results
> in a very nice way to handle time values in Org-mode tables as shown
> below.
>
> Note, the first argument to the `with-time' macro controls whether
> results are returned as a time string or a numerical value.  That
> argument may be followed by any number of expressions.
>
> |  time | miles | minutes/mile |
> |-------+-------+--------------|
> | 34:43 |   2.9 |        11:58 |
> | 56:00 |   5.5 |        10:10 |
> | 31:00 |  3.04 |        10:11 |
> | 32:15 |  2.77 |        11:38 |
> | 33:56 |   3.0 |        11:18 |
> | 72:00 |  6.74 |        10:40 |
> | 52:22 |  4.62 |        11:20 |
> #+TBLFM: $3='(with-time t (/ $1 $2))
>
> #+begin_src emacs-lisp
>    (defun org-time-string-to-seconds (s)
>      "Convert a string HH:MM:SS to a number of seconds."
>      (cond
>       ((and (stringp s)
>             (string-match "\\([0-9]+\\):\\([0-9]+\\):\\([0-9]+\\)" s))
>        (let ((hour (string-to-number (match-string 1 s)))
>              (min (string-to-number (match-string 2 s)))
>              (sec (string-to-number (match-string 3 s))))
>          (+ (* hour 3600) (* min 60) sec)))
>       ((and (stringp s)
>             (string-match "\\([0-9]+\\):\\([0-9]+\\)" s))
>        (let ((min (string-to-number (match-string 1 s)))
>              (sec (string-to-number (match-string 2 s))))
>          (+ (* min 60) sec)))
>       ((stringp s) (string-to-number s))
>       (t s)))
>
>    (defun org-time-seconds-to-string (secs)
>      "Convert a number of seconds to a time string."
>      (cond ((>= secs 3600) (format-seconds "%h:%.2m:%.2s" secs))
>            ((>= secs 60) (format-seconds "%m:%.2s" secs))
>            (t (format-seconds "%s" secs))))
>
>    (defmacro with-time (time-output-p&rest exprs)
>      "Evaluate an org-table formula, converting all fields that look
>    like time data to integer seconds.  If TIME-OUTPUT-P then return
>    the result as a time value."
>      (list
>       (if time-output-p 'org-time-seconds-to-string 'identity)
>       (cons 'progn
>             (mapcar
>              (lambda (expr)
>                `,(cons (car expr) (mapcar #'org-time-string-to-seconds (cdr expr))))
>              `,@exprs))))
> #+end_src
>
> Bastien<bzg@altern.org>  writes:
>
>> Hi Martin,
>>
>> Martin Halder<martin.halder@gmail.com>  writes:
>>
>>> this is fantastic, already love lisp, thanks a lot.. now I have exactly
>>> what I wanted.. additionally I needed the time format in industrial mode
>>> (1h = 100m = 100s), implemented in ihms.
>>
>> thanks for these functions -- I allowed myself to add them to
>> Worg/org-hacks.html, in a new "Times computation" section:
>>
>>    http://orgmode.org/worg/org-hacks.html
>>
>> I added these functions I myself wrote for a particular purpose:
>>
>> #+begin_src emacs-lisp
>> (defun org-hh:mm:ss-string-to-seconds (s)
>>    "Convert a string HH:MM:SS to a number of seconds."
>>    (when (string-match "\\([0-9]+\\):\\([0-9]+\\):\\([0-9]+\\)" s)
>>      (let ((hour (string-to-number (match-string 1 s)))
>> 	  (min (string-to-number (match-string 2 s)))
>> 	  (sec (string-to-number (match-string 3 s))))
>>        (+ (* hour 3600) (* min 60) sec))))
>>
>> (defun org-subtract-hh:mm:ss-time (t1 t2)
>>    "Substract two hh:mm:ss time values."
>>    (let* ((sec (- (org-hh:mm:ss-string-to-seconds t2)
>> 		 (org-hh:mm:ss-string-to-seconds t1)))
>> 	 (hour (floor (/ sec 3600)))
>> 	 (min (floor (/ (- sec (* 3600 hour)) 60)))
>> 	 (secs (round (- sec (* 3600 hour) (* 60 min)))))
>>      (format "%.2d:%.2d:%.2d" hour min secs)))
>> #+end_src
>>
>> With these function, you can subtract durations in a table like this:
>>
>> | Part  |    Begin |      End | Duration |
>> |-------+----------+----------+----------|
>> | One   | 00:00:00 | 00:01:11 | 00:01:11 |
>> | Two   | 00:01:12 | 00:02:00 | 00:00:48 |
>> | Three | 00:02:05 | 00:16:06 | 00:14:01 |
>> #+TBLFM: $4='(org-subtract-hh:mm:ss-time $2 $3)
>>
>> Which was useful for me when I had to derush video files.
>>
>> HTH,
>
>