[Discuss-gnuradio] data size error

[David Saranchak]

Hello,

I am somewhat new to GNU Radio and have a basic programming question. I am not a programmer, so I totally expect this to be obvious... 

I am trying to create a simple MUX block by using existing C++ code blocks and just connecting them in python. One of the first things I am attempting along this route while getting familiar with the code is to MUX two complex streams together, then decimate that stream to obtain one of the original streams. I then desire to multiply by a constant. I define the following:

fg.mux = gr.streams_to_stream(4,2)

fg.decim = gr.keep_one_in_n(4,2) 

fg.amp = gr.multiply_const_cc(1)

then connect them later on:

fg.connect(fg.mux, fg.decim, fg.amp)

I get the following error:

"ValueError: source and destination data sizes are different: keep_one_in_n multiply_const_cc"

Can someone point out to me what I am missing? Or do I need to give you more info?

Also, I realize that there is probably a better, more flexible way to implement a MUX block and am open to suggestions. 

Thanks!

Dave