Re: expfit vs harminv - which is faster/smaller ?

[Sergei Steshenko]

--- On Tue, 12/16/08, Francesco Potortì <address@hidden> wrote:

> From: Francesco Potortì <address@hidden>
> Subject: Re: expfit vs harminv - which is faster/smaller ?
> To: address@hidden
> Cc: address@hidden
> Date: Tuesday, December 16, 2008, 6:18 AM
> >> By reading the docs, it seems to me that they use
> different methods,
> >> are thought for different problems and require
> different inputs:
> >> expfit requires you to give it a number of
> harmonics to find, while
> >> harminv wants a range where to search for them.
> >> 
> >> That said, I should make it clear that I have no
> experience
> >> whatsoever with those methods.
> 
> >This is what I read in 'man harminv':
> >   -f nf Specify a lower bound nf on the number of
> spectral basis
> >   functions (defaults to 100), setting a lower bound
> on the number of
> >   modes to search for.  This option is often a more
> convenient way to
> >   specify the number of basis functions than the -d
> option, above,
> >   which is why it is the default.
> 
> As far as I read, this is a lower bound on the search
> space.  Expinv, on
> the other hand, wants you to tell it exactly how many
> harmonic functions
> it should find.
> 
> -- 
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For me i doesn't matter, i.e. for what I'm doing specifying the minimum
require number of harmonics is good enough.

Practically so far it gives exactly this specified number.

For me the two programs are the same in the sense they both try to
decompose input into a sum of exponentially modulated sinusoids.

Thanks,
  Sergei.