From mboxrd@z Thu Jan 1 00:00:00 1970 From: Carsten Dominik Subject: Re: org-mode feature is surely a bug! Date: Fri, 29 May 2009 16:44:06 +0200 Message-ID: <524EFA67-1D52-4494-92D9-CECD310FA952@gmail.com> References: <20090529142241.GA6173@moocow> Mime-Version: 1.0 (Apple Message framework v935.3) Content-Type: text/plain; charset=ISO-8859-1; format=flowed; delsp=yes Content-Transfer-Encoding: quoted-printable Return-path: Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1MA3Jj-0002nX-UX for emacs-orgmode@gnu.org; Fri, 29 May 2009 10:44:20 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1MA3Jc-0002jd-Na for emacs-orgmode@gnu.org; Fri, 29 May 2009 10:44:16 -0400 Received: from [199.232.76.173] (port=33817 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1MA3Jb-0002jJ-GW for emacs-orgmode@gnu.org; Fri, 29 May 2009 10:44:12 -0400 Received: from mail-ew0-f162.google.com ([209.85.219.162]:54133) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1MA3Jb-0000c7-0F for emacs-orgmode@gnu.org; Fri, 29 May 2009 10:44:11 -0400 Received: by ewy6 with SMTP id 6so7423091ewy.42 for ; Fri, 29 May 2009 07:44:09 -0700 (PDT) In-Reply-To: <20090529142241.GA6173@moocow> List-Id: "General discussions about Org-mode." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: emacs-orgmode-bounces+geo-emacs-orgmode=m.gmane.org@gnu.org Errors-To: emacs-orgmode-bounces+geo-emacs-orgmode=m.gmane.org@gnu.org To: Mike.Dowling@t-online.de Cc: Carsten Dominik , Org Mode List Hi Michael, Thanks for your mail. what version of Org-mode are you using? We have changed this quite some time ago to (float 8) (I see now that the docs still say 5, but this is not the case in the code, it is 8, except maybe in very old releases). The reason why it is not larger is more a display issue and a computation issue. Since Org-mode is pure plain text, we need to write all significant digits into the table, we do not have the option to make the display a shorter version of an underlying more accurate number, and writing out all 16 digits of a double precision number would make the table columns wide and the tables unreadable. We could have #+PRECISION, but you can also do M-x customize-variable RET org-calc-default-modes RET and change it there, for all your files, at least for now, until I have a better option for per-file settings. Hope this helps. Please write next time to emacs-orgmode@gnu.org (this is our mailing list) so that a searchable record of answers and questions is created. Best wishes - Carsten On May 29, 2009, at 4:22 PM, Dr. Michael Dowling wrote: > Hello Carsten, > > I was adapting org-mode to my applications when I noticed that it =20 > could > not add up! I had a table in which one column was a column of =20 > figures, > and I wanted the sum, and org-mode came up with the wrong answer. I =20= > was > flabbergasted when I discovered that this behaviour was documented =20 > as a > feature! > > Specifically, the offending line was > > calc-float-format (float 5) > > Apparently, if the calc default of 12 were used, the tables could look > ugly, so it was thought better to produce a pretty table than a =20 > correct > one! > > At first I thought that this might be merely a display problem, that > internal calculations would be more accurate, and that I could get the > extra precision that I needed using a printf style print, but no. The > printed value indeed had an extra digit, but that right most digit =20 > was a > meaningless '0'. > > I've changed this in my .emacs file, but I would urge a re-think on > this. > > As a numerical analyst, I feel comfortable with rounding errors, and > precision, and I accept that it is impossible to supply exact =20 > answers to > all calculations, but working with only decimal 5 digit precision I =20= > find > rather frightening. (How calc came up with a default of 12 I don't > know; it's capable of arbitary precision, but anything less that the > precision of a double precision of 64 bits (about 16 decimal places), > and all the paraphernalia of guard digits etc. that the hardware > floating point units use is odd.) > > Perhaps a line like > > #+PRECISIOM 21 > > would be nice so that the user can choose his precision on file by =20 > file > basis, and keeping the above value at 12, the calc default. I sixth > digit after a decimal point for a tax return is clearly too much, but > for financial calculations involving millions, this would be > unacceptable. It follows that this really should not be hard coded, =20= > but > set on a file by file basis. > > I don't want to sound negative, though; org-mode is really nifty, and, > although I have still to get into it properly, I have great =20 > expectations > that I am sure will be fulfilled beyond all my hopes! Great work! > > Cheers, > Mike Dowling > > --=20 > Dr. Michael L. Dowling > Gau=DFstr. 27 > 38106 Braunschweig > Germany