[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Discuss-gnuradio] serial_to_parallel and fft_v{f,c}c

From: Patrick Strasser
Subject: Re: [Discuss-gnuradio] serial_to_parallel and fft_v{f,c}c
Date: Thu, 16 Mar 2006 23:44:58 +0100
User-agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.6) Gecko/20050602 Thunderbird/1.0.2 Mnenhy/

Eric Blossom wrote:
On Thu, Mar 16, 2006 at 09:45:05PM +0100, Patrick Strasser wrote:
What is serial_to_parallel doing?
Why is this needed?

The fft_v{f,c}c block is defined to consume and produce a stream of
vectors.  The size of the vectors must be equal to the FFT size.
serial_to_parallel (also known as: serial_to_vector) converts a stream
of items into a stream of (fixed length) vectors of items.

I suppose the underlying flowgraph system uses block processing too, but here we need chunks of a certain and fixed (so to speak "const") size.

Is there anywhere a document or mail describing the data types in an overview?

What is the window flag (3rd parameter) in fft_v{f,c}c for?

It specifies the window to be applied to the data prior to computing the
FFT. See any DSP book for the background. http://comsec.com/wiki?SuggestedReading
Lyons' book is a good place to start.

Windowing is clear to me, but I wasn't able to read the python datatype or gnuradio window type from the C++ .h file. I suppose it's something like gr.firdes.WIN_RECTANGULAR or a vector/list of window coefficients, but I could not figure out exactly until now. Any hints? ;-)

What would be the best way to document all this in a nice end-user-compatible way? (I suppose users should be able to do their programming in python with some form of documentation that is _not_ C++ source code)

There are currently the doxygen generated C++-centric docs.

That's my main resource, giving primary hints and leading to the source files...

The output should be python-centric docs in epydoc output format.
See http://epydoc.sf.net and http://www.stack.nl/~dimitri/doxygen

I've got a patch somewhere in my email that's supposed to do this.
If you're interested in testing it out, I'll dig it out and you can
try it.  If it works, we'll apply it.

I'd really like to try this.

You know, I'm hindered in my wiki-I-want-to-add-more-doc behaviour. Good docs are essential for beginnerns like me, and people used to the system most likely don't see what's _not_ obvious...

Engineers motto: cheap, good, fast: choose any two
Patrick Strasser <patrick dot strasser at  tugraz dot at>
Student of Telematik, Techn. University Graz, Austria

reply via email to

[Prev in Thread] Current Thread [Next in Thread]