🚀 go-pugleaf

On Apr 15, 2:05 pm, Rune Allnor <all...@tele.ntnu.no> wrote:
> On 15 apr, 19:49, Dirk Bell <bellda2...@cox.net> wrote:
>
>
>
>
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> > On Apr 14, 5:10 pm, Rune Allnor <all...@tele.ntnu.no> wrote:
>
> > > On 14 apr, 23:04, Mariya <mariya.nago...@gmail.com> wrote:
>
> > > > Hello:
>
> > > > I have a 4x4 matrix which I wish to decompose into 4 frequency bands
> > > > (LL, HL, LH, HH where L=low, H=high) by using a one-level Daubechies-4
> > > > wavelet transform. As a result of the transform, each band should
> > > > contain 2x2 coefficients. How can I do this in MATLAB? I know that
> > > > MATLAB has dbaux and dbwavf functions. However, I'm not sure how to
> > > > use them and I also don't have the wavelet toolbox.
>
> > > Well, both those functions are from the wavelet toolbox,
> > > so getting that toolbox would be an obvious starting point.
> > > Once you get it, there is a chance that there is some
> > > documentation included, which might help explain how to
> > > use the functions...
>
> > > Rune
>
> > That is an expensive answer if it is gotten legitimately.
>
> I've heard some rumours that matlab has some safety features
> built in, such that a function name from a toolbox you do
> not have a lisence for somehow gets blocked. I haven't tested
> it - don't even know if it is true - but this seems to be a
> 'reasonable' countermeasure against pirate versions of useful
> functions. (Although it would be a nuisance for somebody who
> might want to write a function with a name that happens to be
> taken by a toolbox function.)
>
> So if the OP wants to use those functions mentioned, getting
> the toolbox seems to be the only option.
>
> > Cheaper solution, web search.
>
> Or learning the material from scratch and implement yourself.
> But that was, of course, what you meant...?
>
> Rune- Hide quoted text -
>
> - Show quoted text -

That is what I meant (I like to understand what I use, I have little
faith in unknown apps), but I guess realistically it may not be the
most efficient way.

Dirk