Re: Re: Re: RE: Re: Sometimes <space> means multiple

• To: mathgroup at smc.vnet.net
• Subject: [mg75442] Re: [mg75426] Re: [mg75423] Re: [mg75364] RE: [mg75358] Re: Sometimes <space> means multiple
• From: János <janos.lobb at yale.edu>
• Date: Tue, 1 May 2007 03:19:55 -0400 (EDT)
• References: <200704270918.FAA23598@smc.vnet.net> <200704290714.DAA21234@smc.vnet.net> <200704300738.DAA22373@smc.vnet.net>

```I think the reason for "space" used as multiply is the typical anglo-
american intellectual laziness :)  /Old Hungarian proverb:  "Whose
shirt it is not, should not take it on"/

Steve just did not want to type an extra character when he came up
with the design - that is it.  He was also constrained by the ASCII 7 =

bit.

If I look back on my education for multiplication in elementary
school a dot was use on the "middle of the lane".  On a Mac it is
<Option>+<Shift>+<9>.

Now to use that would have been more painful than just <Shift>+<8>,
wouldn't it ?.

The <Shift>+<8> came to the math circles via computers and with punch =

cards where the restrictive ASCII 7 bit ruled the world and "a" and
"b" had to be tightened with SOMETHING.

Looking many professional journal pdfs one thing is sure.  Neither
the "space" nor the "star" is used for multiplication.  It is still
the dot on the "middle of the lane", a small "x" or nothing.  That
is, I never see "a*b" or "a b" as a multiplication of a and b but
rather I see "ab" or "a=B7b".

With the best,

J=E1nos
P.S.  If I take the "a b" to its ultimate test and "try" it in pre-
fix " ab" or post-fix "ab " that shows clearly the dumbness of the
usage of space in its pure naked form :)

On Apr 30, 2007, at 3:38 AM, Andrzej Kozlowski wrote:

> I compltely agree. I also think that any comparisons between C++ and
> Mathematica in this respect are completely off the mark, unless of
> course sombody decides to develop an analogue of "TradtitionalForm"
> for C++.
>
> I would also like to point out the following obvious but not
> insignificant fact. Enter  a b (or 2 3  if you prefer) and convert to
> InputForm. You will obtain an explicit asterisk in place of the
> space. Conversely, enter a*b and convert to TraditionalForm (or even
> StandardForm). You will get a space instead of the asterisk. This, in
> my opinion,  is exactly how it should be. In fact, I am somewhat
> shocked that anyone would claim otherwise.
>
> Andrzej Kozlowski
>
>
> On 29 Apr 2007, at 16:14, Murray Eisenberg wrote:
>
>> Why "mistake"?  Why not allow Mathematica to mimic as much of
>> traditional mathematical notation as possible without running into
>> genuine ambiguity?
>>
>> After all, it's really convenient to be able to use 2 Exp[x] and
>> Cos[2
>> t] -- and even 2Exp[x] and Cos[2t] -- without having to insert an
>> extra,
>> distracting multiplication symbol.  Then the usage in 2 4, for
>> example,
>> just extends that.
>>
>> In my own work, I ordinarily include an explicit multiplication
>> symbol
>> -- and I prefer the multiplication sign one gets from Esc * Esc
>> of the FORTRANish * -- when the factors are numbers.  There's
>> nothing to
>> prevent you from doing that if you don't like the implicit
>> multiplication indicated by a space.
>>
>>
>> Virgilio, Vincent - SSD wrote:
>>> Personally, I think it was a mistake to overload the meaning of
>>> "space"
>>> to multiply. I bet Wolfram Inc. would reverse that decision now,
>>> if it
>>> wasn't for backward compatibility.
>>>
>>> I like to compare Mathematica to C++. Somewhere in his writings,
>>> Bjarne
>>> Stroustrup mentions the same issue, and his decision not to overload
>>> whitespace. I think the question also arises on the Boost mailing
>>> lists
>>> now and then, mostly tongue-in-cheek.
>>>
>>> (Corrections welcome.)
>>>
>>> Vince Virgilio
>>>
>>> -----Original Message-----
>>> From: Bill Rowe [mailto:readnewsciv at sbcglobal.net]
>>> Sent: Thursday, April 26, 2007 3:35 AM
>>> To: mathgroup at smc.vnet.net
>>> Subject: [mg75364] [mg75358] Re: Sometimes <space> means
>>> multiple , sometimes not
>>>
>>> On 4/25/07 at 5:27 AM, siewsk at bp.com wrote:
>>>
>>>> As a newbie, I was taught that <space> character in Mathematica
>>>> means
>>>> multiple. But sometimes it does not.
>>>
>>>> For example:
>>>
>>> <examples snipped>
>>>
>>> Mathematica allows spaces to be placed before or after any
>>> operation.
>>> Consequently, a space is only interpreted as a multiply when there
>>> is no
>>> other operator or other possible interpretation.
>>>
>>> So, -4 -2 is the same as -4 - 2 or -4-2 and gives -6 but
>>>      -4 (-2) will yield 8
>>> --
>>> To reply via email subtract one hundred and four
>>>
>>> *****************************************************************
>>> This e-mail and any files transmitted with it may be proprietary =
>>>
>>> and are intended solely for the use of the individual or entity to ==

>>>
>>> whom they are addressed. If you have received this e-mail in =
>>>
>>> error please notify the sender. Please note that any views or
>>> opinions presented in this e-mail are solely those of the author =
>>>
>>> and do not necessarily represent those of ITT Corporation. The =
>>>
>>> recipient should check this e-mail and any attachments for the =
>>>
>>> presence of viruses. ITT accepts no liability for any damage =
>>>
>>> caused by any virus transmitted by this e-mail.
>>> *******************************************************************
>>> =0D
>>>
>>
>> --
>> Murray Eisenberg                     murray at math.umass.edu
>> Mathematics & Statistics Dept.
>> Lederle Graduate Research Tower      phone 413 549-1020 (H)
>> University of Massachusetts                413 545-2859 (W)
>> 710 North Pleasant Street            fax   413 545-1801
>> Amherst, MA 01003-9305
>>
>

----------------------------------------------
Trying to argue with a politician is like lifting up the head of a
corpse.
(S. Lem: His Master Voice)

```

• Prev by Date: Re: Simplification
• Next by Date: Plot: write text on a ploted figure, then the figure is covered, why?
• Previous by thread: Re: Re: Map vs. Table
• Next by thread: Re: Re: Re: Re: RE: Re: Sometimes <space> means multiple