Forum: GNU Radio Re: GRC:Suitable Sink required

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Firas A. (Guest)
on 2009-04-20 13:31
(Received via mailing list)

> On Mon, 4/20/09, Saleem A. <removed_email_address@domain.invalid> wrote:
> Hi,
> It appears that gr.message_sink and gr..msg_queues are for
> digital data. but my flowgraph (periodogram) is for analog
> samples,

This is not true (see:

> complex baseband samples from usrp --> stream to vector
> (vectors of fft_size) --> FFT  --> complex to mag squared  --> (sink or
> block to be determined)
> Is their no choice other than file sink?
> Thanks

You can use vector sink.


dst = gr.vector_sink_f()

then you can see the data in this vector by:


Of course you have to run the graph for a while then stop it before
doing the print.

See :


Josh B. (Guest)
on 2009-04-20 20:45
(Received via mailing list)
Ahh, no vector sink. The vector sink will queue up samples forever, and
although you can clear the buffer, you will not stay vector aligned with
the fft size.

Vector sink is good for the QA code with a finite number of samples in
and out, but i would definitely not recommend it for dealing with live
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