Importing filter taps from file (GRC 3.7.1)

GNU Radio
1

Can someone help me to discover why I am not able to import filter taps
from file?

In the attached example, that I am running on GR 3.7.1, I
try to import filter taps from a file (via variable_0) or just typing
some taps (via variable_1).

In the first case I get the following error:

Traceback (most recent call last):
File “/home/piero/top_block.py”, line 74, in
tb = top_block()
File “/home/piero/top_block.py”, line 37, in init
self.fir_filter_xxx_0 = filter.fir_filter_fff(1, (variable_0))
File
“/usr/local/lib/python2.7/dist-packages/gnuradio/filter/filter_swig.py”,
line 1154, in make
return _filter_swig.fir_filter_fff_make(*args, **kwargs)
TypeError: in method ‘fir_filter_fff_make’, argument 2 of type
‘std::vector< float,std::allocator< float > > const &’

I am not able to “decode” the error message.

If I import variable_1 taps everything is OK.

The difference between the two mode seems to be missing commas between
values.

Thank you in advance

Piero

2

I tested your code in GR 3.6.5.1 and I get the same error message. I’m
surprised becouse everithing seems to be right.

http://gnuradio.org/redmine/projects/gnuradio/wiki/GNURadioCompanion

Could anybody help?

Ilaria

3

I found a workaround!!!

I saved the taps as a text file, with entries delimited by a space (by
the way my taps are +1 or -1).

Then I used numpy.genfromtxt(‘filename’,dtype=“float”, delimiter=" ")
directly within the filter dialog or via a variable.

However I am curious to discover why the approach that uses
numpy.fromfile, as indicated in GR manuals, do not work.

regards

Piero