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Re: origin of the index syntax


From: Francesco Potorti`
Subject: Re: origin of the index syntax
Date: Fri, 22 Jul 2005 16:08:33 +0200

>> does anyone know where the index expression syntax used
>> in Octave comes from?  Is the Matlab people who invented it?
>> Or else it is older?
>> Was it just the evolution of something in common usage?
>
>If you mean syntax like 
>
>1:n, :, etc.,
>
>this certainly goes back as far as Matlab and may have been used by
>earlier matrix computation pioneers. 
>
>It is known as 'colon notation' and is described and discussed in Golub
>and Van Loan, Matrix Computations, 3rd Edition, ISBN = 0-8018-5414-8,
>The Johns Hopkins University Press, 1996

Thank you for the reference, which is indeed useful.  Fortran 90, as
already pointed out, has a similar notation.  However, Octave uses a
more powerful syntax for index expressions, where a costant index can be
any of
- a number              (simple notation)
- a colon expression    (colon notation)
- a vector              (Matlab notation?)

As far as I can tell, this was invented by Matlab.  Is that true?

-- 
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