Tag Debug gr_tag_debug from gnuradio import gr gr.tag_debug($type.size*$vlen, $name) set_display($display) Input Type type enum Complex complex size:gr.sizeof_gr_complex Float float size:gr.sizeof_float Int int size:gr.sizeof_int Short short size:gr.sizeof_short Byte byte size:gr.sizeof_char Name name string Num Inputs num_inputs 1 int Vec Length vlen 1 int Display display True bool On True Off False $num_inputs >= 1 $vlen > 0 in $type $vlen $num_inputs