NetNews Usenet Archive 1992 #18/NN_1992_18.iso/spool/comp/sys/hp48/4323

Text File | 1992-08-19 | 5.9 KB | 179 lines

Newsgroups: comp.sys.hp48
Path: sparky!uunet!gumby!destroyer!ubc-cs!unixg.ubc.ca!ochealth
From: [e-mail] (ochealth)
Subject: Re: Hp48 and TI85 compared
Message-ID: <[e-mail]>
Sender: [e-mail] (Usenet News Maintenance)
Nntp-Posting-Host: unixg.ubc.ca
Organization: University of British Columbia, Vancouver, B.C., Canada
References: <[e-mail]>
Date: Thu, 20 Aug 1992 02:33:08 GMT
Lines: 166

In article <[e-mail]> [e-mail] (Rick Homard) writes:
>Hello to all interested in knowing how the TI85 compares with the
>HP48.
>
>This is a (non comprehensive) comparison of the HP48S and the TI85
>available features and commands.
>
>==========================================================================
>
>
>The TI85 supports all boolean operators.  In addition there are commands
>which:  rotate/shift right/left by one bit and conversion between bases.
>
>The HP48 supports all boolean operators, rotate/shift right/left of one
>bit/byte, setting wordsize, 1 bit arithmetic shift right.

in case of confusion, the HP48 does support base conversion. (as long as
it is binary, octal, decimal, or hex) Does the TI85 do arbitrary bases?

>
>
>Solve Applications
>
>Both machines have solve applications.  There is an unusual limitation
>on the TI85 solve application.  It cannot find complex solutions,
>only real solutions.  Not good.

Incorrect! The HP48 solver application can't find complex solutions. If
an equation has a simple linear/quadratic form, you can use ISOL to find
complex solutions

>Plotting and Graphing
>
>The TI85 plots a bit faster than the HP48.

!!!!

>
>The TI85 has better and more zooming features.

hmm, this needs explaining? How is one zoom better? How many ways can you
zoom and pan anyway?
>
>The TI85 has a DiffEq mode of plotting which allows the user to plot
>graphs in terms of "t".
>
>
>Both machines allow you to save plots.
>
>
>Both machines support unit conversions, although the TI85 does not
>support tagged units.
>
>
>Unit Management
>
>Not supported on the TI85.

I assume this means you can't define your own? Can you perform arithmetic
with units?
>
>
>Misc
>
>The TI85 has some features and commands not found on the HP48 (although
>they are readily available via Goodies Disks).
>
>The TI85 has:
>gcd = greatest common divisor
>lcm = least common multiple
>
>=========
>
>The TI85 can solve simultaneous equations (30 unknown maximum).  Indeed
>the HP48 can do this also but it does not have a user interface to do it
>from.  A nice feature but slow when solving anything larger than 15 unknowns.

Simultaneous Linear equations? The HP48 can solve these, and more that 30 too.
(assuming memory permits)
>
>============
>
>The TI85 also has a built in polynomial root finder (order =< 30).  A nice
>interface but the root finder is terribly slow when the order of the
>polynomial is large.
>I compared the TI85's root finder with the HP48 (using the root finding
>program supplied by Bill Wickes on the net).  The results are incredible.
>The same 30th order polynomial was input to each machine.  The HP48 found
>all of the roots in 80 seconds.  I stopped the TI85 after 15 minutes.
>It is obvious that the TI85 gets heavily labored when required to perform
>at its limits.

Can the TI85 find roots of complex polynomials? Wickes can't, but with a
little trick (any Wayne`s POLY utils) it can.
>
>=========
>
>The TI85 can also do sequences of sums or products.  I know that the HP48
>can do summation sequences but I don't believe that has the (built in)
>capability of doing sequences of products.

 'exp( sum(a,b,ln(product series) ) )' ;-) OK, that's pushing it!
>
>========
>
>The TI85 has an interpolation environment.  You provide two known pairs
>of data ( (x1,y1) and (x2,y2) )  and one known, either x or y and it will
>calculate the unknown.

This has an equivalent in the STATs menu. (with linear regression)
>
>===========
>
>The TI85 performs some fudging (rounding, et al) on calculations.
>
>Examples:
>
>0.333333333333 * 3 = 1
>and
>sin (3.14159265359) = 0

If I remember TI, they don't really round the answer, they just display
part of the answer (ie the first 12 digits, and the 13 and 14 are kept
internally). Sort of like the HP with 10 FIX on all the time, but trailing
zeros aren't displayed.
>
>The TI85 also performs numerical integration and differentiation in the
>graphical environment.

How fast is it? Does it return an error estimate? I had a TI56 that did
Simpson's rule, and it was SLOW. When it finished you had NO CLUE whether
the answer is meaningful. The HP uses an adaptive algorithm which will
usually return usefull results to an integral, and give you a good idea
whether the numerical result is close, or way off.
>
>===========
>
>Well that's all I have for now.  If anybody has anything to add please
>notify me so I will know as well.
>

Is there any way to "get inside" the TI85? I mean software wise. A lot
of power in the HP48 comes from being able to add low level machine language
programs that blow away any user level program. For example, the recent ML
FFT is blindingly fast, and it can't be done quickly in user code.



Well, I won't be trading in my 48SX, but it bugs me that the TI85 has built
in matrix stuff the HP doesn't (eigenvalues, LU etc). That stuff is nasty
to write, and I'd rather have it built in (even though I can add that easily
from the NET). I think the HP48 has some White Elephant code that was put
in for marketing: like the equation writer. It sure looks cool on the box,
but I rarely use it. I'd rather have some extra functions, or Matrix things
or Polynomial things built in instead. (AT least I can add them!)

>
>Rick Homard
>


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