The Museum of HP Calculators

HP Forum Archive 20

 10bii+ Trig BugMessage #1 Posted by Katie Wasserman on 5 July 2011, 10:50 p.m. I was just thinking about what the 10bii+ would be like as a re-purposed RPN calculator and playing around with it when I found a trig bug. Try this in degrees mode: ```270 SIN (you'll correctly get -1.00) 270 TAN (you'll see OFLO flash and get correctly get -1.00E500) 270 COS (you'll correctly get 0.00) 270 TAN (you'll see OFLO flash and get 1.00E500 -- the bug) ``` This is in version 7-13-2010. I hope that this is the only bug, I use the 10bii+ a bunch and find it to be a really nice (if non-RPN) machine. -Katie p.s. There's still a yet-to-be-found Easter Egg in there. Edited: 5 July 2011, 10:51 p.m.

 Re: 10bii+ Trig BugMessage #2 Posted by Tim Wessman on 5 July 2011, 11:51 p.m.,in response to message #1 by Katie Wasserman I have not been able to reproduce the sign change thing. Is that what you are referring to? Or the fact that it does the overflow and then returns a number? 270 is undefined as it is an infinity sign change. Could you please explain more? TW Edited: 5 July 2011, 11:52 p.m.

 Re: 10bii+ Trig BugMessage #3 Posted by Katie Wasserman on 6 July 2011, 1:24 a.m.,in response to message #2 by Tim Wessman Correct, I am referring to the sign change. In the first case the TAN of 270 returns -1.00E500 in the second it returns +1.00E500. You need to do these steps in the order I wrote starting with a ALL CLEAR. I can reproduce this on both 10bii+ calculators that I have. I realize that TAN 270 is infinite but in one case it's negative infinity and the other it's positive infinity. Apparently the sign of the last result obtained before the TAN function is the determining factor. More.... Actually, it turns out that an overflow condition always carries over the sign from the previous calculation. This happens even for something like factorial, for example: ```1 - 2 = 300 ! ``` results in -1.00e500 The 10bii (not +) results in +1.00e500 Edited: 6 July 2011, 1:54 a.m.

 Re: 10bii+ Trig BugMessage #4 Posted by Thomas Radtke on 6 July 2011, 5:21 a.m.,in response to message #1 by Katie Wasserman A side note: It would be very esthetic to omit a (likely wrong) result at all on overflow. Edited: 6 July 2011, 5:21 a.m.

 Re: 10bii+ Trig BugMessage #5 Posted by Katie Wasserman on 6 July 2011, 11:42 a.m.,in response to message #4 by Thomas Radtke I agree and I believe that the 20b/30b takes this approach. However the 10bii+ was intended to replace the 10bii and needs to be upwardly compatible with it in all respects. One of which is just flashing OFLO and returning 1e500 when an overflow occurs.

 Re: 10bii+ Trig BugMessage #6 Posted by Thomas Radtke on 6 July 2011, 5:01 p.m.,in response to message #5 by Katie Wasserman Yes, the 20b at least omits it. Just noticed the german error message on overflow (300!): "Keine Amortisation". Strange.

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