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From: Han on 16 Mar 2010 22:48
I got my HP 50G about a week ago, and have been playing with its
features and the CAS. While the machine is a wonderful "tinkering"
tool, I find that it still falls short as a reliable calculator. The
erratic / inconsistent behavior of the CAS and related flags coupled
with the slowdown resulting from the 12MHz <-> 75MHz swap (I read
about this here on comp.sys.hp48), it seems that even after 3
generations (HP 49G, HP 49G+, and now HP 50G), HP still does not have
it quite together. =(

Can anyone shed some light on the history of the HP 49 -> HP 49G+ ->
HP 50G series in terms of hardware changes as well as operating
systems? Every now and then I would read a post that mentions Kenpo
OS... are there now several operating systems, and not just the
software emulating the Saturn CPU?

Getting back to the CAS, I find it odd that there is nothing in ROM
that essentially saves a user's settings, does calculations with
whatever necessary flags set/unset, and then restores the user's
settings. For example, when I evaluate a limit, flag -115 is cleared.
There is nothing that indicates this until I later use the square root
operation. Then there's the auto-prompting for complex mode; some
operations require it be turned off, and others require it be turned
on. Otherwise I get an error... I often think: why not just "do what
you have to do" and return the original state (flagwise)?

Other inconsistencies include special placement of inputs for sigma in
the equation writer, but the limit operator essentially uses algebraic
notation regarding inputs. The outputs of various calculations are
also inconsistent. For example:

4 5 XROOT

produces e^( 2ln(2) / 5 )... while mathematically correct, it is
completely inconsistent with other inputs. Anyway, that's all for now.

From: Virgil on 16 Mar 2010 23:40
In article
<b10815d5-3124-4b32-bcc7-540283dc6fb1(a)k17g2000yqb.googlegroups.com>,
Han <handuongster(a)gmail.com> wrote:

> I got my HP 50G about a week ago, and have been playing with its
> features and the CAS. While the machine is a wonderful "tinkering"
> tool, I find that it still falls short as a reliable calculator. The
> erratic / inconsistent behavior of the CAS and related flags coupled
> with the slowdown resulting from the 12MHz <-> 75MHz swap (I read
> about this here on comp.sys.hp48), it seems that even after 3
> generations (HP 49G, HP 49G+, and now HP 50G), HP still does not have
> it quite together. =(
>
> Can anyone shed some light on the history of the HP 49 -> HP 49G+ ->
> HP 50G series in terms of hardware changes as well as operating
> systems? Every now and then I would read a post that mentions Kenpo
> OS... are there now several operating systems, and not just the
> software emulating the Saturn CPU?
>
> Getting back to the CAS, I find it odd that there is nothing in ROM
> that essentially saves a user's settings, does calculations with
> whatever necessary flags set/unset, and then restores the user's
> settings. For example, when I evaluate a limit, flag -115 is cleared.
> There is nothing that indicates this until I later use the square root
> operation. Then there's the auto-prompting for complex mode; some
> operations require it be turned off, and others require it be turned
> on. Otherwise I get an error... I often think: why not just "do what
> you have to do" and return the original state (flagwise)?


If you want a program, or a series of commands, to end with all the same
flag settings and in the same directory as when it began, merely start
it with a PUSH command and end it with a POP command.
>
> Other inconsistencies include special placement of inputs for sigma in
> the equation writer, but the limit operator essentially uses algebraic
> notation regarding inputs. The outputs of various calculations are
> also inconsistent. For example:
>
> 4 5 XROOT
>
> produces e^( 2ln(2) / 5 )... while mathematically correct, it is
> completely inconsistent with other inputs. Anyway, that's all for now.
From: John H Meyers on 16 Mar 2010 23:52
On 3/16/2010 9:48 PM, Han wrote:

> Every now and then I would read a post that mentions Kinpo OS...
> are there now several operating systems,
> and not just the software emulating the Saturn CPU?

My mental image (which may be too low-resolution to be accurate :) is

Kinpo: Hardware (incl tester and flash updater) and emulator, in separate bank of ROM.

HP: Saturn ROM banks (slightly doctored to employ some emulator-level things)

> Getting back to the CAS, I find it odd that there is nothing in ROM
> that essentially saves a user's settings, does calculations with
> whatever necessary flags set/unset, and then restores the user's settings.

Just like leaving the eggs to be added at home to a cake mix,
which Betty Crocker knew would make the home cook feel more involved,
HP knows that you will feel more involved if you do this yourself :)

You can, for example, use

PUSH [then do anything] POP

or you can use an automatic 'BetaENTER' program,
such as mentioned in some old postings
(which are older now than I am, which means that
I can't possibly have made them myself :)

http://groups.google.com/group/comp.sys.hp48/msg/a5716f4bf1cca011
(towards the end)

http://groups.google.com/group/comp.sys.hp48/msg/9eb78e7553ecc545

> Then there's the auto-prompting...

See flag -120 (automatically handled in above 'BetaENTER' program)

> 4 5 XROOT

What answer do you want?

[r->] [OFF]
From: Han on 17 Mar 2010 01:14
> My mental image (which may be too low-resolution to be accurate :) is
>
> Kinpo: Hardware (incl tester and flash updater) and emulator, in separate bank of ROM.
>

If this is really the case, that's just sad...

> Just like leaving the eggs to be added at home to a cake mix,
> which Betty Crocker knew would make the home cook feel more involved,
> HP knows that you will feel more involved if you do this yourself :)

Only I feel like I bought the latest and greatest blender, and am
finding out that making a smoothie followed by making a slushy could
potentially cause future smoothies to be have a different texture --
maybe even end up with a "roughie."

>
> You can, for example, use
>
> PUSH [then do anything] POP
>

Thank you for this fix. Is there any reason why this IS NOT the
default behavior? I am starting to feel like I have to write all these
small utilities to "fix" what should never even be "broken." I am
starting to feel sorry for any new user of the HP 50G.

> > 4 5 XROOT
>
> What answer do you want?

The same output that I would get for any other set of inputs such as 5
6 XROOT. If you enter 4 5 XROOT, you get e^(2ln(2) / 5) whereas 5 6
XROOT you get XROOT(6,5). Why is there this inconsistency? Either keep
them both at XROOT(X,Y) or both in the form e(LN(Y)/X).

Here's an example of what I encounter often -- something working in
"most" cases but fails in a general case:

'2*LN(3)+5*LN(7)' LNCOLLECT results in: LN(3^2*7^5)
'2*LN(X)+5*LN(Y)' LNCOLLECT results in: LN(X^2*Y^5)

but

'A*LN(X)+B*LN(Y)' LNCOLLECT does nothing... (I am aware that this is
the same behavior in Erable as well).

Another example:

'X*(X+1)' EXPAND produces 'X^2+X'
and
'A*(B+C)' EXPAND produces A*B+A*C'

whereas

'X*(Y+1)' EXPAND does nothing on the HP 50G but works as expect on the
HP 48G. (BTW, replacing EXPAND with EXPAN gives me the same results).
Well, it turns out that the CAS actually treats 'X*(Y+1)' as a
polynomial, so that EXPAND (or EXPAN) doesn't actually do anything
except to reorder the expression as '(Y+1)*X'. Except when you look at
the AUR it explains that EXPAND and EXPAN expand products and has a
misleading example showing '(X+Y)^2' expanding as 'X^2+2*Y*X+Y^2'.

And yes, I am aware of the command DISTRIB (which apparently is what I
really want). I just wish the documentation was a bit more clear on
how algebraic objects are handled. As far as I know, there is no
documentation on this behavior in any of the manuals.

As for flag -120... this is just sad. Whatever happened to being able
to work with complex numbers and yet still expect "real" results. As
an example:

'X^2/(X^4+1)' INTVX results will vary depending on the complex mode.
This itself is fine. But it is impossible to specify no simplification
over the complex reals and still be able to work w/ complex numbers.
That is, I cannot work with complex numbers and expect 'X^2/(X^4+1)'
INTVX to give me a result over R[X] at the same time. This would not
be a problem on the HP48 and Erable installed.

I could go on and on about what a "normal" user (regardless of prior
experience with TI and/or HP calculators) might expect and how they
could get frustrated by this calculator. I am just glad I have the
patience to keep pushing forward in learning the ins and outs of this
thing.
From: Virgil on 17 Mar 2010 01:56
In article
<cc50ca3e-3b55-48bc-a00b-83d7536bb6f7(a)a18g2000yqc.googlegroups.com>,
Han <handuongster(a)gmail.com> wrote:

> > My mental image (which may be too low-resolution to be accurate :) is
> >
> > Kinpo: Hardware (incl tester and flash updater) and emulator, in separate
> > bank of ROM.
> >
>
> If this is really the case, that's just sad...
>
> > Just like leaving the eggs to be added at home to a cake mix,
> > which Betty Crocker knew would make the home cook feel more involved,
> > HP knows that you will feel more involved if you do this yourself :)
>
> Only I feel like I bought the latest and greatest blender, and am
> finding out that making a smoothie followed by making a slushy could
> potentially cause future smoothies to be have a different texture --
> maybe even end up with a "roughie."
>
> >
> > You can, for example, use
> >
> > PUSH [then do anything] POP
> >
>
> Thank you for this fix. Is there any reason why this IS NOT the
> default behavior?

Yes! If it were the default, there would be no way for a program to
modify the system or user flags for use by other programs.

I, for one, would find that "cure" much worse than the disease.

> I am starting to feel like I have to write all these
> small utilities to "fix" what should never even be "broken." I am
> starting to feel sorry for any new user of the HP 50G.
>
> > > 4 5 XROOT
> >
> > What answer do you want?
>
> The same output that I would get for any other set of inputs such as 5
> 6 XROOT. If you enter 4 5 XROOT, you get e^(2ln(2) / 5) whereas 5 6
> XROOT you get XROOT(6,5). Why is there this inconsistency? Either keep
> them both at XROOT(X,Y) or both in the form e(LN(Y)/X).
>
> Here's an example of what I encounter often -- something working in
> "most" cases but fails in a general case:
>
> '2*LN(3)+5*LN(7)' LNCOLLECT results in: LN(3^2*7^5)
> '2*LN(X)+5*LN(Y)' LNCOLLECT results in: LN(X^2*Y^5)
>
> but
>
> 'A*LN(X)+B*LN(Y)' LNCOLLECT does nothing... (I am aware that this is
> the same behavior in Erable as well).
>
> Another example:
>
> 'X*(X+1)' EXPAND produces 'X^2+X'
> and
> 'A*(B+C)' EXPAND produces A*B+A*C'
>
> whereas
>
> 'X*(Y+1)' EXPAND does nothing on the HP 50G but works as expect on the
> HP 48G. (BTW, replacing EXPAND with EXPAN gives me the same results).
> Well, it turns out that the CAS actually treats 'X*(Y+1)' as a
> polynomial, so that EXPAND (or EXPAN) doesn't actually do anything
> except to reorder the expression as '(Y+1)*X'. Except when you look at
> the AUR it explains that EXPAND and EXPAN expand products and has a
> misleading example showing '(X+Y)^2' expanding as 'X^2+2*Y*X+Y^2'.
>
> And yes, I am aware of the command DISTRIB (which apparently is what I
> really want). I just wish the documentation was a bit more clear on
> how algebraic objects are handled. As far as I know, there is no
> documentation on this behavior in any of the manuals.
>
> As for flag -120... this is just sad. Whatever happened to being able
> to work with complex numbers and yet still expect "real" results. As
> an example:
>
> 'X^2/(X^4+1)' INTVX results will vary depending on the complex mode.
> This itself is fine. But it is impossible to specify no simplification
> over the complex reals and still be able to work w/ complex numbers.
> That is, I cannot work with complex numbers and expect 'X^2/(X^4+1)'
> INTVX to give me a result over R[X] at the same time. This would not
> be a problem on the HP48 and Erable installed.
>
> I could go on and on about what a "normal" user (regardless of prior
> experience with TI and/or HP calculators) might expect and how they
> could get frustrated by this calculator. I am just glad I have the
> patience to keep pushing forward in learning the ins and outs of this
> thing.
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