[PD] measuring entropy of a signal?

[ronni montoya]

Hi, why is not possible? Instead of analysing the real time value of
the signal , maybe i can have  a memory or buffer  that store the a
piece of signal ( groups of samples) from time to time and then
analize that group of values.

Maybe it can convert that group of values into a string and then:

http://www.shannonentropy.netmark.pl/calculate



Other idea : ive seen using shannon entropy for calculating complexity
in terms of spatial configuration.

Maybe other option could be converting my signal into image for
example using similarity matrix and then analyze that image to get
entropy values.




cheers


R





2013/2/26, Charles Z Henry <czhenry at gmail.com>:
> Hi Ronni
>
> How do you mean to do it?
>
> Shannon entropy is not an independent measurement--the information in a
> observation is relative to the distribution of all it's possible values.
>
> If I just take one sample and it's evenly distributed between -0.98 and 1
> and it's quantized in 0.02 increments (to make the math easier), then the
> information of any value observed is:
> -0.01*log(0.01)
>
> Then--if I had a signal that's N samples long, I have N times as much
> information.  Or perhaps think of it as a rate of information.
>
> But for real numbers and continuous distributions, this doesn't work.  The
> information in a single observation diverges.  So, doing that with floating
> point numbers is not practical.
>
> You often see Shannon entropy describing digital signals.  If the signal
> just switches between 0 and 1, we can generate a distribution of the data
> and see what the probability is empirically.  The entropy of each new
> sample is relative to the distribution.  Likewise, then if you know the
> maximum rate of switching, you can figure out the maximum rate of
> information in the signal.
>
> Just a few thoughts...
>
> Chuck
>
>
>
> On Tue, Feb 26, 2013 at 6:09 AM, ronni montoya
> <ronni.montoya at gmail.com>wrote:
>
>> Hi , i was wondering if anybody have implemented the shannon entropy
>> function in pd?
>>
>> Do anybody have tried measuring entropy of a signal?
>>
>>
>> cheeers
>>
>>
>>
>> R.
>>
>> _______________________________________________
>> Pd-list at iem.at mailing list
>> UNSUBSCRIBE and account-management ->
>> http://lists.puredata.info/listinfo/pd-list
>>
>