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Full Version: A curious output from the HP-35s
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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!

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

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.

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 :)

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

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

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.

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

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

Regards,

John

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.

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

Fresh graduates, fresh graduates, and paying customers.

Stefan

d:D

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

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

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