The Museum of HP Calculators

HP Forum Archive 18

[ Return to Index | Top of Index ]

A curious output from the HP-35s
Message #1 Posted by Palmer O. Hanson, Jr. on 7 Dec 2008, 9:08 p.m.

In Algebraic and Fix 1 mode enter the following complex arithmetic problem:

(6 + 3i) - (4 + 6i)

Press ENTER and see 2.0+-3.0i in the display.

Bizarre!

      
Re: A curious output from the HP-35s
Message #2 Posted by Chuck on 7 Dec 2008, 9:32 p.m.,
in response to message #1 by Palmer O. Hanson, Jr.

I see 2.0i-3.0. No stranger than entering 2+-3i and hitting enter. It looks strange, but the i just separates the real and imaginary parts.

Edited: 8 Dec 2008, 8:51 a.m. after one or more responses were posted

            
Re: A curious output from the HP-35s
Message #3 Posted by Karl Schneider on 7 Dec 2008, 11:53 p.m.,
in response to message #2 by Chuck

Palmer -

I get Chuck's result, which looks strange to me. I assert that

2.0i-3.0

is improperly formatted, as it appears to be (2.0*i) - 3.0.

In "compact" form, the number ought to be displayed as

2.0-i3.0

Now, here's the way to do it:

The HP-42S would display this result more clearly as

2.0 -i3.0

whereas the polar-format result is displayed as

3.6 /-56.3

Note that the negative sign precedes the "i" (as it should), while the negative sign follows the angle symbol (as it should). "i" is a multiplicative operand, while the angle symbol is not.

-- KS

Edited: 8 Dec 2008, 1:38 a.m.

                  
Re: A curious output from the HP-35s
Message #4 Posted by Walter B on 8 Dec 2008, 1:44 a.m.,
in response to message #3 by Karl Schneider

The way the 42S displays complex data is the best I know on HP calcs. No troubles with +- following each other immediately, no strange elevated - signs, just ... simply correct :)

                  
Re: A curious output from the HP-35s
Message #5 Posted by Palmer O. Hanson, Jr. on 9 Dec 2008, 2:45 a.m.,
in response to message #3 by Karl Schneider

Quote:
I get Chuck's result, which looks strange to me.
I can't get Chuck's result unless I am in RPN mode. Am I missing something?

Palmer

                        
I found it!
Message #6 Posted by Chuck on 9 Dec 2008, 9:32 a.m.,
in response to message #5 by Palmer O. Hanson, Jr.

In algebra mode, under display settings there is an option 11. This gives a+bi form. Why not in RPN mode hp?

That was a fun Easter egg.

Chuck

                              
Re: I found it! ... was in Datafile a good while ago
Message #7 Posted by Gene Wright on 9 Dec 2008, 2:42 p.m.,
in response to message #6 by Chuck

which is mentioned in the 35s review published in datafile and on hpcc.org as well as being mentioned in the 35s learning modules! :-)

Perhaps a+bi is just too "un-RPN" to be in anything other than algebraic.

But, these complex number display modes are mentioned in Datafile V26 Special 35s Issue on page 6.

                                    
Re: I found it! ... was in Datafile a good while ago
Message #8 Posted by Palmer O. Hanson, Jr. on 9 Dec 2008, 9:50 p.m.,
in response to message #7 by Gene Wright

Quote:
Perhaps a+bi is just too "un-RPN" to be in anything other than algebraic.

But, a display of a + - b i is un-anything!

Palmer

                                          
Re: I found it! ... was in Datafile a good while ago
Message #9 Posted by John B. Smitherman on 9 Dec 2008, 10:38 p.m.,
in response to message #8 by Palmer O. Hanson, Jr.

It makes you wonder who's designing, writing and testing the software these days.

Regards,

John

                                                
Re: I found it! ... was in Datafile a good while ago
Message #10 Posted by Stefan Vorkoetter on 10 Dec 2008, 4:26 p.m.,
in response to message #9 by John B. Smitherman

Quote:
...who's designing, writing and testing the software these days.

Fresh graduates, fresh graduates, and paying customers.

Stefan

                                                      
Re: I found it! ... was in Datafile a good while ago
Message #11 Posted by Walter B on 10 Dec 2008, 5:35 p.m.,
in response to message #10 by Stefan Vorkoetter

d:D

May I say I second your statement though I do not welcome it? d;)

                                                
Re: I found it! ... was in Datafile a good while ago
Message #12 Posted by V-PN on 11 Dec 2008, 6:53 p.m.,
in response to message #9 by John B. Smitherman

Not me - I would have certainly detected the defect. HP people and affiliates still don't see what's wrong...

                                          
Re: I found it! ... was in Datafile a good while ago
Message #13 Posted by Gene Wright on 10 Dec 2008, 12:56 p.m.,
in response to message #8 by Palmer O. Hanson, Jr.

Perhaps. But I have seen many ways of displaying complex numbers.

(0,1) 10THETA30 5i6 and I do remember 5+6i, which is how they were written in my algebra books. The issue is with the unary negative sign in this instance.

The 35s provides multiple display formats for complex numbers, which are quite useful (in spite of the badly formed theta character).

Don't like a display format? Then choose another. :-)

On a more serious note, I do hope everyone is doing well in these challenging times.

                                                
Re: I found it! ... was in Datafile a good while ago
Message #14 Posted by Karl Schneider on 11 Dec 2008, 1:00 a.m.,
in response to message #13 by Gene Wright

Quote:
The 35s provides multiple display formats for complex numbers, which are quite useful (in spite of the badly formed theta character).

Don't like a display format? Then choose another. :-)


Hi, Gene --

All I would require are cartesian and polar display formats that are clear and mathematically correct, like the HP-42S formats I listed earlier in this thread. I have no desire for the "ordered parenthesized pair" format used in the RPL-based models and the HP-71B.

And an angle symbol should be utilized -- not a theta, which looks too much like a 0 or 8, and is generally used to denote an angular variable itself, not that the value that follows is an angle.

-- KS


[ Return to Index | Top of Index ]

Go back to the main exhibit hall