pylint: fix warnings (mostly import-related)

amodem/__main__.py

@@ -1,14 +1,18 @@
 #!/usr/bin/env python
 # PYTHON_ARGCOMPLETE_OK
-from . import main, calib, audio, async
-from .config import bitrates
-from . import version
-
+import argparse
+import logging
 import os
 import sys
 import zlib
-import logging
-import argparse
+
+from . import async
+from . import audio
+from . import calib
+from . import main
+from . import version
+from .config import bitrates
+
 
 # Python 3 has `buffer` attribute for byte-based I/O
 _stdin = getattr(sys.stdin, 'buffer', sys.stdin)
@@ -97,6 +101,7 @@ def get_volume_cmd(args):
         for c in volume_controllers:
             if os.system(c['test']) == 0:
                 return c[args.command]
+    return None
 
 
 def wrap(cls, stream, enable):

amodem/async.py

@@ -1,8 +1,9 @@
 """Asynchronous Reading capabilities for amodem."""
 
-import threading
-import six  # since `Queue` module was renamed to `queue` (in Python 3)
 import logging
+import threading
+
+import six  # since `Queue` module was renamed to `queue` (in Python 3)
 
 log = logging.getLogger()
 

amodem/calib.py

@@ -1,15 +1,16 @@
 """Calibration capabilities for amodem."""
 
+import itertools
+import logging
+import subprocess
+
+import numpy as np
+
 from . import common
 from . import dsp
 from . import sampling
 from . import stream
 
-import numpy as np
-import itertools
-import logging
-import subprocess
-
 log = logging.getLogger(__name__)
 
 
@@ -104,6 +105,7 @@ def volume_calibration(result_iterator, volume_ctl):
 
 
 def iter_window(iterable, size):
+    # pylint: disable=stop-iteration-return
     block = []
     while True:
         item = next(iterable)

amodem/common.py

@@ -4,9 +4,10 @@ Commom utilities and procedures for amodem.
 """
 
 import itertools
+import logging
+
 import numpy as np
 
-import logging
 log = logging.getLogger(__name__)
 
 scaling = 32000.0  # out of 2**15
@@ -74,6 +75,7 @@ def take(iterable, n):
 
 def izip(iterables):
     """ "Python 3" zip re-implementation for Python 2. """
+    # pylint: disable=stop-iteration-return
     iterables = [iter(iterable) for iterable in iterables]
     while True:
         yield tuple([next(iterable) for iterable in iterables])

amodem/detect.py

@@ -1,14 +1,15 @@
 """Signal detection capabilities for amodem."""
 
+import collections
+import itertools
+import logging
+
+import numpy as np
+
 from . import dsp
 from . import equalizer
 from . import common
 
-import numpy as np
-import logging
-import itertools
-import collections
-
 log = logging.getLogger(__name__)
 
 

amodem/dsp.py

@@ -55,10 +55,9 @@ def coherence(x, omega):
     n = len(x)
     Hc = exp_iwt(-omega, n) / np.sqrt(0.5*n)
     norm_x = norm(x)
-    if norm_x:
-        return np.dot(Hc, x) / norm_x
-    else:
+    if not norm_x:
         return 0.0
+    return np.dot(Hc, x) / norm_x
 
 
 def linear_regression(x, y):

amodem/equalizer.py

@@ -1,12 +1,13 @@
 """Audio equalizing capabilities for amodem."""
 
+import itertools
+
+import numpy as np
+
 from . import dsp
 from . import sampling
 from . import levinson
 
-import numpy as np
-import itertools
-
 
 class Equalizer(object):
 

amodem/framing.py

@@ -1,10 +1,11 @@
-from . import common
-
+import binascii
 import functools
 import itertools
-import binascii
-import struct
 import logging
+import struct
+
+from . import common
+
 log = logging.getLogger(__name__)
 
 

amodem/main.py

@@ -1,6 +1,8 @@
-import numpy as np
-import logging
 import itertools
+import logging
+
+import numpy as np
+
 from . import send as _send
 from . import recv as _recv
 from . import framing, common, stream, detect, sampling

amodem/recv.py

@@ -1,14 +1,15 @@
+import functools
+import itertools
+import logging
+import time
+
+import numpy as np
+
 from . import dsp
 from . import common
 from . import framing
 from . import equalizer
 
-import numpy as np
-import logging
-import itertools
-import functools
-import time
-
 log = logging.getLogger(__name__)
 
 
@@ -49,10 +50,10 @@ class Receiver(object):
         log.debug('Prefix OK')
 
     def _train(self, sampler, order, lookahead):
-        Nfreq = len(self.frequencies)
         equalizer_length = equalizer.equalizer_length
         train_symbols = self.equalizer.train_symbols(equalizer_length)
-        train_signal = self.equalizer.modulator(train_symbols) * Nfreq
+        train_signal = (self.equalizer.modulator(train_symbols) *
+                        len(self.frequencies))
 
         prefix = postfix = equalizer.silence_length * self.Nsym
         signal_length = equalizer_length * self.Nsym + prefix + postfix
@@ -138,7 +139,7 @@ class Receiver(object):
 
     def _update_sampler(self, errors, sampler):
         err = np.array([e for v in errors.values() for e in v])
-        err = np.mean(np.angle(err))/(2*np.pi) if len(err) else 0
+        err = np.mean(np.angle(err))/(2*np.pi) if err.size else 0
         errors.clear()
 
         sampler.freq -= self.freq_err_gain * err

amodem/sampling.py

@@ -1,8 +1,8 @@
-#!/usr/bin/env python
-import numpy as np
 import itertools
 
-from amodem import common
+import numpy as np
+
+from . import common
 
 
 class Interpolator(object):

amodem/send.py

@@ -1,11 +1,12 @@
+import itertools
+import logging
+
+import numpy as np
+
 from . import common
 from . import equalizer
 from . import dsp
 
-import numpy as np
-import logging
-import itertools
-
 log = logging.getLogger(__name__)
 
 

amodem/tests/test_framing.py

@@ -8,6 +8,7 @@ import pytest
 def concat(iterable):
     return bytearray(itertools.chain.from_iterable(iterable))
 
+
 r = random.Random(0)
 blob = bytearray(r.randrange(0, 256) for i in range(64 * 1024))
 

amodem/tests/test_sampling.py

@@ -20,6 +20,6 @@ def test_resample():
 
 
 def test_coeffs():
-    I = sampling.Interpolator(width=4, resolution=16)
-    err = I.filt[0] - [0, 0, 0, 1, 0, 0, 0, 0]
+    interp = sampling.Interpolator(width=4, resolution=16)
+    err = interp.filt[0] - [0, 0, 0, 1, 0, 0, 0, 0]
     assert np.max(np.abs(err)) < 1e-10

tox.ini

@@ -1,5 +1,5 @@
 [tox]
-envlist = py27,py34
+envlist = py27,py3
 [testenv]
 deps=
 	pytest
@@ -10,6 +10,6 @@ deps=
 	six
 commands=
 	pep8 amodem/ scripts/
-	pylint --extension-pkg-whitelist=numpy --report=no amodem --rcfile .pylintrc
+	pylint --extension-pkg-whitelist=numpy --reports=no amodem --rcfile .pylintrc
 	coverage run --source amodem/ --omit="*/__main__.py" -m py.test -v
 	coverage report