A21

Hello.  A while back, I wrote a small integration document to tackle
some integrals that the 49G could not solve automatically (if you are
interested, search Google Groups for [49G]: Integration: A Student's
Perspective).  I have not seen too many new posts about the 49G not
being able to solve such and such an integral symbolically.  If you
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polynomial systems symbolically using the HP 49G CAS.  When I say
trouble I mean I cannot get the calculator to solve these particular
systems by itself (these systems, of course, can be solved by simple
substitutionsmanipulations on the user's part).  My question is not
necessarily can I solve these equations (which is an obvious yes), but
why does the 49G have problems with these systems.  Here are two
examples:
(1) ['Y^2=2*X' 'X^2=Y'] ['X' 'Y'] SOLVE
(2) ['S^3-T^3=A' '3*S*T'=B'] ['S' 'T'] SOLVE
Both of these systems result in the infamous Unable to factor
message and are returned unevaluated.  One of my questions is, what
exactly does this message mean (as I have received it in all sorts of
symbolic calculations)?  In this case, is it a by-product of internal
manipulations done by the Grobner basis engine?  Or is it something
else?  Second, why is it that the 49G cannot solve these sets of
equations by its own (compared to, say, the TI-89 which can do both of
these automatically)?  I agree it is a great strength of the 49G CAS
to allow you to manipulate expressions easily in hopes of finding an
answer when the 49G fails, but I am having trouble understanding why
these equations cannot be solved when they seem so simple.  Perhaps it
was intentionally left this way for some reason  (perhaps to save
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HI!
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I am trying to back up the contents of my home directory ( and
associated sub-directories).
I am using the PC connectivity kit 3.0r4 connected to my PC.
I am using RPN mode on the calculator( the only mode that should be
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I agree that this is an excellent idea.  By the way, if you need any
assistance, I would love to help out.  I have been using the 49G for
over a year now (not counting how long I have used the emulator before
that) and I still consider myself a beginner.  This would be a great
addition to the FAQdocumentation world for the HP 49G.  One thing I
would like to stress is that there should be a good deal about the CAS
(perhaps you disagree?), which is the most confusing subject for a
document a while back, but I do not know if it would be useful to the
beginner, or an intermediate user.  If you would like to see it,
search for [49G]: Integration: A Student's Perspective on Google and
tell me what you think (you can use it if you like it; or if you think
it is crap, give me some feedback so I can make it better! :-).  In
any case, I would like to emphasize that this is something that could
really help new users, and may even catch the eye of those who want to
know more about the HP 49G before they purchase one.  Well, I guess I
am just about done rambling...
  best wishes,
--Rahul Hor216
They worked in the WEIGHT3 program;
perhaps the reference supplied earlier by Bob Wheeler
(who supplied these formulas)
might contain a better explanation.
Bob said: Set SW(0)=SX(0)=M(0)=0 so assume W(0)=0 also.
HP seems to use the terminology population (of all the observations)
variance, which goes to zero, and sample (predicted from
observations) variance, which goes to infinity at N=1.
To make a confusing comedy routine out of this, we might say that
the population variance means of the sample, while the sample
variance means of the entire population -- that's why I only
choose by which is larger and which is smaller,
and don't try to remember what it's called :)
But Mycroft is a very precise mathematician,
and won't settle for just getting the right answers,
the way engineers do ;)
 
uhm... talking about conflicts: they remark so much the difference between
dividing by N-1 and by N, when they also recommend to use a very large N,
otherwise the stats are meaningless...
 
However Bob's formulas should be slightly slower than the ones I had, since
they use 1 division per iteration, while I use 2 divisions at the end (but
don't ask me about numerical precision): and if N is greater than 2... ;)
 
Has anyone got Bjorn Gahm's REM34BG to work with a NAD amplifer?
CYNOX is a German Co .  ?   Has huge RAM versions of 48GX .
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By the last I'll assume that you've loaded everything correctly.
Here's working source:
% UPCASE
C=DAT1 A
?C#0 A
SKIPYES
{ % Too few args!
  LA 00201
  GOVLNG 05023
}
CD1EX
A=DAT1 A
D1=C
LC 02A2C % (string)
?A=C A
SKIPYES
{ % Bad arg type!
  LA 00202
  GOVLNG 05023
}
CD1EX
RSTK=C
CD1EX
C=DAT1 A
D1=C
D1+5
C=DAT1 A
C-5
CDEX A
R0=C A
C=D A
DSRB A
D-1 A
GOTOC End
D1+3
{
  D1+2
  C=DAT1 B
  LA 61 % (ascii a)
  ?C<A B
  GOYES .NextChar
  LA 7A % (ascii z)
  GOYES .NextChar
  CBIT=0 5
  DAT1=C B
  *.NextChar
  D-1 A
  UPNC
}
*End
C=R0 A
D=C A
C=RSTK
D1=C
A=DAT0 A
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    The command ASM don`t modify the string, i just get the error :
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I'm currently having a problem with my HP49G
During the boot process I am getting the warning invalid card data
then the CAS message followed by the Meta Kernal grob then finally the
algebraic stack with edit menu. At any key press the calc reboots with
the same error.
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I have had both an Hp48GX and an HP48G for years. They both followed
as an upgrade from a trusty 32SII. The HP48GGX gave me what seemed
back then
as an infinite amount of space (32K128K)to program and deal with
complex numbers and functions by adopting directly the complex
notation for s=jw and hence any powers of it thereof something that
the 32S could not do since you always had to splitform complex
numbers into real and imaginary parts and the stack was no more than 4
levels. I work as a development electrical engineer and my field of
work requires the analysis of electric networks and the solution of
linearnonlinear systems often with complex coefficients in some
derivations for filter design. The potential of the 48GX goes far
beyond that of the 32S by giving you access to list processing that
may contain other lists with any objects, again another term that
was new to me,etcetera...
machine gained a great deal of speed in most previously weak areas
(such as equation writer, built-in editor, filer etc.)
Then came the HP49G that had twice the RAM of the 48GX and 1.256MB
port memory.
far better than the one built-in the 48GX (without Alg48 or Erable).
This time the matrices could contain anything just like the lists and
not just complex numbers! I could have permanently a whole bunch of
stuff in my calc beyond technical things like various databases with
persons and books and yes, even games! The two most troublesome things
have been the plastic screen cover and the lack of infrared port. I
have removed the cover and the viewing improved dramatically but he
risk of damage is greater now. I must be careful.
So, there it is, a small summary of my experience. Think about it,
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(snip)
Probably part-advertisement.  Who cares what it looks like?
It's a really good calculator, though.  I don't understand why
you'd buy the HP48GX instead of it.  The 49G can do everything
the 48GX can, and the 49G is much faster and has more memory.
I saw them priced together in one store, and the difference
there was negligible.  See hpcalc.org for more information.
Regarding support, most documentation on the HP48GGX applies
to the HP49G, with some translation in entry points.  UserRPL
programs are no problem.  Programs that use different entry
points need to be translated.  Programs that are compiled and
use different entry points could be decompiled, patched, and
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Thomas Rast escribi227:
Well, I think prefix. Am I too bizarre? I don't think so. When I see
an infix expression such as '3+5' I analize it, look for the topmost
operator (or function, or whatever), make a search in my database to
know how many operands it takes, then analize each of those operands...
and finally I do the operations. That is, for the example above:
'+', which takes two operands, one before the sign, the other after it
(that's because the expression is represented in infix.
first operand: 3
second: 5
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Should I take that as a threat?  If it it, it's not a very good one, or 
very
mature either.
I admit that I did wrong by calling one individual who assumed that he knew
everything a smartass.  You were never part of it, nor should you take
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In the equation I'm using, there's no such a thing as exact value,
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example mentioned in AUG book
d1Y(X)+2*Y(X)=EXP(3*X,Y(X))
DESOLVE
for y'(x)+2*y(x)=e^(3*x)
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How do you enter d1Y(X) using RPN? The only way I can enter it is using the
Equation Editor. I receive a syntax error when entering Y(X) on the stack.
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How do you enter d1Y(X) using RPN? The only way I can enter it is using the
Equation Editor. I receive a syntax error when entering Y(X) on the stack.
to
syntax to
useless.
There's