A quick question on tags.
I’m coding a custom block in python and my forecast function is like so:
def forecast(self, noutput_items, ninput_items_required):
#setup size of input_items[i] for work call
for i in range(len(ninput_items_required)):
ninput_items_required[i] = 64
If my understanding is correct, every 64 items, the block’s work
Each time work is called, I want to add a tag to the first of the 64
elements that come in (the value of my tag is a list). So I used:
lst = (1, 2, 3, 4) #example
item_index = 0 offset = self.nitems_written(0) + item_index key = pmt.string_to_symbol("example") value = pmt.to_pmt(lst) self.add_item_tag(0, offset, key, value)
This works. I can see the tag being added when I use a QT time sink.
But when I add some print statements and check what I noticed is that
are being added at indicies 0, 8192, 16384 etc. Basically multiples of
which is the full length of the input buffer in0 = input_items.
Shouldn’t self.nitems_written(0) be 64 each time?
What I really want is tags being added at 0, 64, 128 etc. I’m sure I’m
missing something pretty silly.