Re: no way for simple matrix lookup ?

[Julius Smith]

How about A(diag(b',c)) ?

-- jos

At 10:33 AM 6/16/2004, D. Goel wrote:

> Mike, that doesn't work, your recipe below is the first thing I tried.
>
> Example, A = [1 3; 2 4]
> b=c=[1 2].
>
> The answer needed is [1 4], but both of your answers below give me [1
> 2 3 4].
>
>
> Mike Miller <address@hidden> writes:
>
>
> > D = A(b,c)
> >
> > And your variable D will be a matrix with size(D)=[length(b),
> > length(c)]. You can transform it into a vector using D=D(:), or you
> > can do this:
> >
> > D = reshape(A(b, c), length(b)*length(c), 1)
> >
> > You don't have to loop over 'i'.
> >
> > Best,
> >
> > Mike
> >
> >
> >
> [...]
>
>
>
>
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_____________________________
Julius O. Smith III <address@hidden>
Assoc. Prof. of Music and (by courtesy) Electrical Engineering
CCRMA, Stanford University
http://www-ccrma.stanford.edu/~jos/



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Octave is freely available under the terms of the GNU GPL.

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