Re: not equivalent?

[Paul Kienzle]

On Thu, Nov 07, 2002 at 03:46:15PM -0500, Albert F. Niessner wrote:
> 
> I have two vectors (series and spacing) of 500x1 elements each. If I
> then do the following (N = length(series);):
> 
>   k=0:N-1;
>   W = e.^(-j*2*pi*(spacing*k)/N);
>   spectrum = W' * series;
               ^^
This is the complex conjugate.

> 
> I get some answer. Because of the size of W, it may be worth while to
> loop over very large vectors so I can also do it this way:
> 
>   w = -j*2*pi*spacing/N;
>   for k=1:N
>     W = e.^(w*(k-1));
>     spectrum(k) = sum (series .* W);
                                   ^

This is not.

>   endfor;

Use W.' to transpose without conjugate.

Does this help?

Paul Kienzle
address@hidden



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