35s revision?


I am in the market for a new scientific calculator and recently came across the 35s on HP's site. I did a little bit of research on it (mostly on this forum) and gather that there is a bug in the cos() calculations. Is there any information as to when an update that corrects this will be? or is there a way around it by using the sin() function and a trig identity? Sorry if this is a common / already answered question. Thanks for the help.


The cos(x) bug is more a loss of significant figures near x=90. I doubt it will be fixed any time soon since the problem is also in the 33s and has been know about for ages.

I also doubt it is a significant problem for normal use of the calculator. Hence, it hasn't been fixed.

- Pauli


Rick --

Bugs stemming from calculation of sine and cosine of arguments far from zero -- but where the result is very near zero -- were introduced in the HP-33s and carried forward to the HP-35s. However, the bug was not discovered and reported in time to be corrected for either model.

The following MoHPC Forum post of mine was in a thread provided in electronic form by me directly to HP's lead calculator R&D person at the 2007 HHC Conference. I would certainly expect that any future revised version of the HP-35s will include a remedy for this bug:

HP-33s & 35s trigonometric bug tabulated

It's true, though, that the bug is not very serious. Results are still correct to at least six significant digits.

-- KS

Edited: 23 Apr 2008, 11:38 p.m.


Is there any information as to when an update that corrects this [cos() loss of significant digits] will be?

Others have addressed the impact of the cos() glitch, but generally speaking, and judging by past experience, HP will probably quietly issue a bug-fixed 35s sometime in the next six months. It happened that way with the 33s -- only that one was more obvious since the updated calculator had a different display as well. (Actually, there was a production run with the new display, but old ROM; search the archives for the gory details.)

There is an article which lists known and suspected first-generation 35s bugs and annoyances. It shouldn't be too difficult to check a new calculator against that list (well, most of it).



Thanks for the replies. If HP does decide to issue an updated ROM is there any way to re-flash the one on board? Or would you have to purchase a new one?


If HP does decide to issue an updated ROM is there any way to re-flash the one on board?

No. The 35s really has ROM, not flash, EEPROM or anything reprogrammable. You would have to buy a new calculator to get it.


Possibly Related Threads…
Thread Author Replies Views Last Post
  HP Prime - Revision Suggestion - Setting the Clock Bill Triplett 5 2,149 11-15-2013, 12:36 AM
Last Post: Joe Horn
  New revision of the PowerCL & Manual Ángel Martin 2 2,289 06-11-2013, 01:43 AM
Last Post: Ángel Martin
  HEPAX Revisited: Revision 1E available Ángel Martin 4 1,603 05-03-2013, 01:57 PM
Last Post: Diego Diaz
  CL-UTILS revision 2G released Ángel Martin 4 1,612 01-08-2012, 03:40 PM
Last Post: Ángel Martin
  WP-34S Revision 1653 Feedback svisvanatha 6 1,893 10-03-2011, 02:54 AM
Last Post: Walter B
  HP 82153A WAND revision 1E versus 1F Pierre Hardy 1 997 05-21-2008, 12:42 PM
Last Post: Massimo Gnerucci (Italy)
  HP-42S Revision Level John Horak 9 2,300 05-15-2005, 06:08 AM
Last Post: Matthias
  82104A Card Reader (revision 1F) bug? Brian Ayling 3 1,097 07-10-2004, 01:58 AM
Last Post: Vieira, Luiz C. (Brazil)
  HP 82973 revision A Miki Mihajlovic 3 1,087 02-23-2004, 03:35 AM
Last Post: Christoph Klug
  HP-71B System ROM Revision History Philip 5 1,430 12-08-2002, 08:17 PM
Last Post: Gordon Dyer

Forum Jump: