The Museum of HP Calculators

HP Forum Archive 18

 HP50g plotting questionMessage #1 Posted by MikeO on 5 Sept 2008, 2:32 a.m. Hmm. When I attempt to plot y1(X)=ABS(SIN(X)), I get full sine curve in the plot display. I would expect all positive values from this function - and thus a series of "humps" in the positive Y, positive X area. The plot seems to ignore the ABS function. Any ideas why? Thanks, MikeO

 Re: HP50g plotting questionMessage #2 Posted by MikeO on 5 Sept 2008, 3:04 a.m.,in response to message #1 by MikeO Hmm. I turn on "rigorous" mode and it fixes the graph. I think that's the right answer. Thanks, MikeO

 Re: HP50g plotting questionMessage #3 Posted by Don Shepherd on 5 Sept 2008, 7:33 a.m.,in response to message #2 by MikeO Hmmm. So "non-rigorous" = mathematically incorrect? That's bothersome.

 Re: HP50g plotting questionMessage #4 Posted by MikeO on 5 Sept 2008, 10:08 a.m.,in response to message #3 by Don Shepherd That's about the size of it! ;) I thought it was strange as well. Perhaps there is some narrow domain/range in complex number functions, or certain algebras, where |X| should be considered X, but I'm not sure what they would be. MikeO Edited: 5 Sept 2008, 10:09 a.m.

 Re: HP50g plotting questionMessage #5 Posted by Hal Bitton in Boise on 5 Sept 2008, 11:22 a.m.,in response to message #1 by MikeO I've gone the rounds with this a time or two myself. With rigorous de-selected, you can manually use the "ABS" function, but that's about it...ABS will not work programmatically or in an expression. The manual says "The CAS can solve a larger variety of problems if the rigorous mode is not set. However, the result, or the domain in which the result are applicable, might be more limited." Not sure why this is...perhaps one of our resident math guru's could shed some light on this. Best regards, Hal

 Re: HP50g plotting questionMessage #6 Posted by MikeO on 5 Sept 2008, 5:10 p.m.,in response to message #5 by Hal Bitton in Boise Yes, I'd love to hear if someone has a good explanation of why this is a useful option. I wish I had an "accept false premise" option on the calculator. Then I could prove any theorem with it. A powerful feature indeed! MikeO

 Re: HP50g plotting questionMessage #7 Posted by Chotkeh Software Corporation on 30 Sept 2008, 1:47 p.m.,in response to message #1 by MikeO On our site there is an example of plotting covered. You will find it under Quick Start. A simple solution, but it may help. We have a few free PDFs which may help you in the process of learning the 50G. Owner.

 Re: HP50g plotting questionMessage #8 Posted by hpnut on 1 Oct 2008, 4:24 a.m.,in response to message #7 by Chotkeh Software Corporation Quote: On our site there is an example of plotting covered. You will find it under Quick Start. A simple solution, but it may help. We have a few free PDFs which may help you in the process of learning the 50G. Owner. Hello, thanks for alerting me to your website. Under your "Functions" PDF, I learned that the SPC key also works like the ENTER key. I never knew that. sigh, if only HP had made one big SPC/ENTER key :-( hpnut in Malaysia Edited: 1 Oct 2008, 4:24 a.m.

 Re: HP50g plotting questionMessage #9 Posted by Chotkeh Software Corporation on 1 Oct 2008, 11:20 a.m.,in response to message #8 by hpnut Well they are separate keys because at some points they also have there own functions.

 Re: HP50g plotting questionMessage #10 Posted by Chotkeh Software Corporation on 1 Oct 2008, 11:26 a.m.,in response to message #9 by Chotkeh Software Corporation We will have another Free PDF File, which will be on our site within a week. It will cover the key functions of the device. You will find it under "About the HP 48GII, 50G, & 49G+ Graphing Calculators" Even though the devices user's manual covers this, we cover it a little further in detail.

Go back to the main exhibit hall