"y \= scalar" fails

[Rolf Fabian]

Jaroslav Hajek-2 wrote:
> 
> On Mon, Mar 3, 2008 at 1:42 PM, Rolf Fabian <Rolf.Fabian at gmx.de> wrote:
>>  Jaroslav Hajek-2 wrote:
>>  >
>>  > this seems 100% correct.
>>  > y \= c means y = y \ c = inv(y) * c,
>>  >
>>
>>  Thanks for explaining me, what a backslash
>>  division is supposed to do.
> 
> Unfortunately, I didn't. The inv(y)*c thinkg was a mistake; it does
> not work that way.
> y \= c is indeed equivalent to y = y\c, the rest is not true.
> "Supposed to" is the problem here. Supposed by whom?
> 
> -- 
> RNDr. Jaroslav Hajek
> computing expert
> Aeronautical Research and Test Institute (VZLU)
> Prague, Czech Republic
> url: www.highegg.matfyz.cz
> 

Did I write "how a backslash division is supposed to work"
or did I actually specify "what a backslash division is supposed
to do" ? You should better recognize the difference.

The fact, that for an (invertible) square matrix y and scalar c
the command "y \= c" results in a size conflict error looks weird and
obscure to me. Moreover, the fact that MatLab behaves in the same
way does  not all all make this 'feature' less strange and less obscure.
The way how the calculation is actually done does not play
any role concerning that statement.

Again:
In my eyes, having to specify

"y \= c * eye( size (y))"
(for square y and constant c)

instead of "y \= c" 

to get something which is 'conceptually identical'
to "y \= c" 

is extremely ugly and needs to be improved
by allowing syntax "y \= c" for that special
case.


-----
Rolf Fabian
<r dot fabian at jacobs-university dot de>

-- 
View this message in context: http://www.nabble.com/%22y-%5C%3D-scalar%22-fails-tp15799910p15807075.html
Sent from the Octave - Bugs mailing list archive at Nabble.com.