There are a few cases when input_items[0] doesn't equal input_items[1]. If say, len(input_items[0]) = 1000 and len(input_items[1]) = 1500, and I returned the smaller of the two values, 1000, what would happen to the other 500 samples on port 1? Would they be buffered somewhere and then used the next time the work function is called?
On Wed, Aug 1, 2012 at 8:40 PM, Tom Rondeau <t...@trondeau.com> wrote: > On Wed, Aug 1, 2012 at 3:46 PM, Alexander Olihovik <ano...@virginia.edu> > wrote: > > Hi all! > > I'm writing a custom sink block in Python with multiple input ports of > all > > the same data type. > > I've been reading Josh's block coding guide, but I'm confused at one > point: > > The value returned by a block should be the number of items produced by > that > > block. > > Is this to say that if I have multiple ports, I may return the value of > > input_items[0]? > > Or is it correct to say that I must return the sum of all > input_items[i], i > > = range(number of input ports)? > > > > > > I would like to create a synchronous block where all ports consume and > > produce an equal number of items every time the work function is called. > > However, it appears that there are times when input_items[0] != > > input_items[1] != ... != input_items[numPorts-1] > > If I were to return input_items[0], I would assume that this would not > yield > > the results I expect! > > > > Any help is greatly appreciated! > > > > From, > > Alex > > If you have a block with multiple input items and you want to produce > the same number every time, noutput_items will tell you how much you > are capable of producing on every output stream. When you 'return > noutput_items', you are saying that you have produced that many items > on EVERY stream. > > There is another way that specifies the same thing. Each block > consumes some number of samples on every input stream and produces > some number of samples on every output stream. You can individually > specify "produce(i, N_i)" and "consume(o, N_o)" on each input and > output stream, respectively. In this case i is the input stream and > N_i is the number of items consumed on that input stream and o is the > output stream and N_o is the number of items consumed on that output > stream. When specifying your own 'produce' values, though, make sure > to return WORKED_CALLED_PRODUCE, to tell the scheduler that you have > done this yourself. But it sounds like you want to produce the same > amount on every stream, so you should be fine just using 'return > nouput_items'. > > Tom > -- *Alex Olihovik University of Virginia 2013 BS Electrical Engineering BS Computer Engineering ano...@virginia.edu*
_______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
