Xref: utzoo comp.lang.smalltalk:830 comp.lang.c++:2370
Path: utzoo!attcan!uunet!mcvax!unido!laura!exunido!georg
From: georg@exunido.uucp (Georg A. M. Heeg)
Newsgroups: comp.lang.smalltalk,comp.lang.c++
Subject: Re: Smalltalk versus C++
Keywords: object-oriented languages
Message-ID: <831@laura.UUCP>
Date: 6 Jan 89 23:35:21 GMT
References: <447@ubbpc.UUCP> <824@laura.UUCP> <451@ubbpc.UUCP>
Sender: root@laura.UUCP
Reply-To: georg@unido.UUCP (Georg A. M. Heeg)
Organization: Georg Heeg Dortmund, W-Germany
Lines: 44

In article <451@ubbpc.UUCP> wgh@ubbpc.UUCP (William G. Hutchison) writes:
>  This is interesting, but not exactly the _type_ of answer I was looking for.
>It seems to me that you may be using dynamic classes because they are _there_,
>not because you really need them.  Could your applications be written using
>statically declared classes?  Are dynamic classes necessary for application
>development in a structured "software engineering" sort of way, or just handy
>for improvising programs at the terminal?
>
It is not necessary (you can simulate a turing machine in c and thus in c++ :-))
but really handy: William mentions "development". You can really develop
interactively a program try notions (classes) try hierarchies and redesign
them. To my opinion software development is a creative process with a lot of
design and redesign cycles and improvising is often a valuable first step to
get a rough idea of a new application field.
 
......
> Is this literally true?  What about checking values for "close to zero"
>in pivoting?  Complex numbers are not well-ordered, so you probably want to
>check if the magnitude of the number is close to zero.

Close to 0 means: | a(i,j) | < epsilon (in mathematical notaion)

In Smalltalk-80-Notation

	(a at: i@j) abs < epsilon

Certainly abs is differently defined for real and complex numbers.


> Thanks for the info.  Does anybody know if one of the inexpensive Smalltalk
>implementations runs correctly on the AT&T 6300PLUS (80286) ???

Smalltalk-80 is a large memory system and you can hardly address 4 or 8 MB
with 16 bit addresses of a 80286 linearly. You need a 80386 to run it.
It is available since december 88 from ParcPlace Systems, Palo Alto,
e-mail: sales@ParcPlace.com or from us (for Germany, BeNeLux, Austria and
Switzerland) and this version runs under MS-DOS.

May be somebody recommends to you Smalltalk-V, I don't.

Georg Heeg 
Smalltalk-80 Systeme 
Baroper Str. 337 
D-4600 Dortmund 50