On Fri, Oct 2, 2009 at 12:07 PM, Carlo DiCelico <carlo.dicel...@gmail.com> wrote: > I saw an article on O'Reilly about using NumPy and Dislin to analyze > and visualize WAV files. It's a really fantastic article but was a > little out of date. I updated the script to work with the newer > modules &etc but am still having trouble getting it working. > > The line > > temp[i,:] = array(struct.unpack("%dB"%(fft_length), tempb),Float) - > 128.0 > > always returns the same error: "Traceback (most recent call last): > File "pysono.py", line 31, in <module> > temp[i,:] = array(struct.unpack("%dB"%(fft_length),tempb),float) - > 128.0 > struct.error: unpack requires a string argument of length 256" when I > do python pysono.py test.wav 256 > > I'm sure it's probably something simple but I just can't see what it > is! > > Here's the original code: > http://onlamp.com/python/2001/01/31/graphics/pysono.py > > Thanks!
In: struct.unpack("%dB" % (fft_length), tempb) tempb is not length 256. Also, note that (foo) is the same as just foo. To create a tuple of length 1 you must say (foo,) HTH, ~Simon -- http://mail.python.org/mailman/listinfo/python-list