Hi Pedro,

$y[n]=\sum\limits_{i=n-N+1}^n {\left|x[i]\right|^2}$ is nothing but the
moving average over the squared magnitude.
Sadly, your formula
$T=\sum\limits_{n=0}^{N-1} {\left|Y[n]\right|^2}$ doesn't specify what T
signifies; is T used as a single sum over N samples' squared magnitudes,
or is it something running (i.e. you get as many Ts as you consider samples.

I just assume you really are looking for a moving average, in which case
your flow graph is correct.
> Timothée told me to use stream to vector, but if I pack them, each 100
> samples will become one single information, right? What I need is more
> like a controller that gives me 100 samples at a time.
Really, I'm not sure where the formula you attached came from, or what
you mean, or if what you mean is what you need...
Maybe you could just write down, explicitely, what *each* output sample
should be (which is why I wrote $y[n]$ rather than $y$).


Best regards,
Marcus


On 12.01.2016 17:27, Pedro Gabriel Adami wrote:
> Dear all,
>
> In addition to my previous response, I'm attaching an image that shows
> the formula I'm trying to build in gnuradio (using blocks). But
> instead of n = 0 and N-1, I need n = 1 and 100 (100 samples). The
> second picture shows how I tried to do in Gnuradio, but the moving
> average block does not get 100 samples the way I need (as we could see
> in the previous answers).
>
> Timothée told me to use stream to vector, but if I pack them, each 100
> samples will become one single information, right? What I need is more
> like a controller that gives me 100 samples at a time.
>
> Please, I appreciate if you could give me some tips.
>
> Thanks in advance.
>
> 2016-01-08 14:47 GMT-02:00 Timothée COCAULT
> <timothee.coca...@gmail.com <mailto:timothee.coca...@gmail.com>>:
>
>     Whoops, just noticed I didn't reply to all when I answered so my
>     message and Pedro's response were not forwarded to the mailing list :
>
>     Le jeu. 7 janv. 2016 à 20:28, Pedro Gabriel Adami
>     <pedrogabriel.ad...@gmail.com
>     <mailto:pedrogabriel.ad...@gmail.com>> a écrit :
>>
>>     Dear, Timothée,
>>
>>     Thank you so much. I am doing some tests and I've realized that
>>     the results are a little strange. That is why I asked.
>>
>>     Let me ask you one more thing: Do you know some block that is
>>     capable to retain N samples, so I can use them and after that, it
>>     retains the next N samples? Like a variable where I can "save"
>>     the information for a short period of time, but my Gnuradio does
>>     not have a "variable sink".
>>
>>     Thanks in advance.
>>
>>     Em 07/01/2016 17:18, "Timothée COCAULT"
>>     <timothee.coca...@gmail.com <mailto:timothee.coca...@gmail.com>>
>>     escreveu:
>>
>>         Hi Pedro,
>>
>>         When you're not sure, the best solution is often to look at
>>         the code.
>>         If you look at the work function in
>>         gr-blocks/lib/moving_average_XX_impl.cc.t, you see that the
>>         block first sums the history (of length 100 in your case).
>>         For each additional input items, it adds the new item and
>>         subtracts the n-100 item, and outputs the current sum.
>>
>>         So it will first calculate 1+...+100, then 2+...+101 and so on.
>>
>>         Regards,
>>         Timothée. 
>>
>>          
>>
>>
>
>     I don't understand exactly your question but you can use a stream
>     to vector to group your items in packets of size N, and plug it
>     into a probe signal
>
>
>
>
> -- 
> Atenciosamente,
> Pedro Gabriel Adami
> Graduando do 5º período de Engenharia de Controle e Automação no
> Instituto Nacional de Telecomunicações - Inatel
>
>
> _______________________________________________
> Discuss-gnuradio mailing list
> Discuss-gnuradio@gnu.org
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