Re: [Discuss-gnuradio] Error trying to load FFT filter taps

[Tom McDermott]

Thanks, Tom   that solved the problem.

numpy.fromfile('filename', numpy.complex64).tolist()

Should the gnuradio wiki (GRC) text be updated?

Apologies for the triple posting, first two attempts were using yahoo.com mail account, got

bit by the yahoo DMARC problem and dumped from the list. Changed to gmail to avoid the problem.

-- Tom, N5EG

On Sun, Apr 20, 2014 at 8:44 AM, Tom Rondeau <address@hidden> wrote:

On Sat, Apr 19, 2014 at 1:27 PM, Tom McDermott <address@hidden> wrote:

Am getting the following error when trying to run a GRC flowgraph that loads FFT filter taps from an external file. The type filter parameter is set to complex->complex (complex taps).

The flow graph has imported numpy.  The taps are loaded using:

numpy.fromfile('/home/tom/Desktop/EchoScreencaps/chirp-down-20-20-131072', numpy.complex64)

as the taps parameter.  What does the error below mean?

GRC: v3.7.4git-101-g76970d54

Ubuntu 13.10

top_block.py is attached.

-- Tom, N5EG

Traceback (most recent call last):
  File "/home/tom/Desktop/EchoScreencaps/top_block.py", line 173, in <module>
    tb = top_block()
  File "/home/tom/Desktop/EchoScreencaps/top_block.py", line 115, in __init__
    self.fft_filter_xxx_0 = filter.fft_filter_ccc(1, (numpy.fromfile('/home/tom/Desktop/EchoScreencaps/chirp-down-20-20-131072', numpy.complex64)), 1)
  File "/usr/local/lib/python2.7/dist-packages/gnuradio/filter/filter_swig.py", line 1329, in make
    return _filter_swig.fft_filter_ccc_make(*args, **kwargs)
TypeError: in method 'fft_filter_ccc_make', argument 2 of type 'std::vector< gr_complex,std::allocator< gr_complex > > const &'

Tom,

This is a conflict between the numpy array data type and swig. Call the .tolist() function on the array passed back from numpy and it should work.

Tom