Re: getting freqz from fft (complex numbers)

Rune Allnor wrote:
> * This is the L0 or L1 norm of the spectrum, I never remember the
> correct term.

It should be easy to remember the correct term because an L0 norm
doesn't exist.

> The nice thing about norms is that if
> ||x|+|y||>||x|+|z||
> in one norm, it is also true in all other norms. So the
> computationally
> cheap norms can be used to find the extrema, and the usual
> L2 norm can be used only where one wants to know the details.

That won't work, Rune. Consider the two numbers z1=1.0, z2=.9 exp(i
pi/4). Then

||z1||_L2 > ||z2||_L2

but

||z1||_L1 < ||z2||_L1

Regards,
Andor

.

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