Closes #5 Python 3.3/3.4 compatible

.travis.yml

@@ -5,6 +5,8 @@ os:
 python:
 - '2.6'
 - '2.7'
+- '3.3'
+- '3.4'
 install:
 - pip install -r requirements.txt
 - pip install coveralls

CHANGES.md

@@ -2,12 +2,22 @@
 
 ### develop (unreleased)
 
+### v0.2 (August 7, 2014)
+
+#### Enhancements
+
+- Made Python 3.3/3.4 compatible [#5][]
+
 ### v0.1 (August 7, 2014)
 
 #### Enhancements
 
 - Add Travis-CI testing [#1][]
 - Create invoke tasks to automate PyPi deploy [#2][]
+- Made PEP8 compliant [#3][], [#4][]
 
 [#1]: https://github.com/questrail/sdfascii/issues/1
 [#2]: https://github.com/questrail/sdfascii/issues/2
+[#3]: https://github.com/questrail/sdfascii/issues/3
+[#4]: https://github.com/questrail/sdfascii/issues/4
+[#5]: https://github.com/questrail/sdfascii/issues/5

README.md

@@ -4,8 +4,8 @@
 [![PyPi Version][pypi ver image]][pypi ver link]
 [![Coverage Status][coveralls image]][coveralls link]
 
-A Python (2.6+) module for reading Standard Data Format (SDF) and ASCII
-files saved by HP/Agilent Dynamic Signal Analyzers (DSA).
+A Python (2.6+/3.3+) module for reading Standard Data Format (SDF) and
+ASCII files saved by HP/Agilent Dynamic Signal Analyzers (DSA).
 
 The HP/Agilent 35670A Dynamic Signal Analyzer has the ability to save
 files as either SDF or ASCII format.

requirements.txt

@@ -6,3 +6,4 @@ numpy==1.8.1
 pep8==1.5.7
 pyflakes==0.8.1
 pypandoc==0.8.2
+six==1.7.3

sdfascii.py

@@ -11,7 +11,7 @@
 
 # Try to future proof code so that it's Python 3.x ready
 from __future__ import print_function
-# from __future__ import unicode_literals
+from __future__ import unicode_literals
 from __future__ import division
 from __future__ import absolute_import
 
@@ -23,16 +23,22 @@
 # Data analysis related imports
 import numpy as np
 
-__version__ = '0.1'
+import six
 
+__version__ = '0.2'
 
-def _strip_nonprintable(input_string):
+
+def _strip_nonprintable(input_bytes):
     '''
     (str) -> str
 
-    Return input_string without nonprintable characters
+    Return string without nonprintable characters
+
+    Actually this take a bytes object and converts it to a string only
+    returning any character up to but not including the first instance of
+    "\x00"
     '''
-    return input_string.split('\x00', 1)[0]
+    return input_bytes.decode(errors="replace").split('\x00', 1)[0]
 
 
 def _convert_sdf_unit_to_dictionary(sdf_unit):
@@ -88,8 +94,12 @@ def read_ascii_files(input_ascii_base_filename):
     ydata = np.loadtxt(ascii_ydata_filename)
 
     # Return the x and y data as a structured array
-    return np.core.records.fromarrays([xdata, ydata],
-                                      names='frequency,amplitude')
+    if six.PY2:
+        return np.core.records.fromarrays(
+            [xdata, ydata], names=b'frequency,amplitude')
+    elif six.PY3:
+        return np.core.records.fromarrays(
+            [xdata, ydata], names='frequency,amplitude')
 
 
 def _decode_sdf_file_hdr(record_size, binary_data):
@@ -144,6 +154,9 @@ def _decode_sdf_meas_hdr(record_size, sdf_revision, binary_data):
     Decode the measurement header binary data
     '''
     meas_hdr = {}
+    record_size_from_binary_data = struct.unpack('>l', binary_data[2:6])[0]
+    if record_size != record_size_from_binary_data:
+        sys.exit('Bad record size in SDF_MEAS_HDR')
     meas_hdr['record_size'] = record_size
     (meas_hdr['offset_unique_record'],) = struct.unpack(
         '>1l', binary_data[6:10])
@@ -157,8 +170,7 @@ def _decode_sdf_meas_hdr(record_size, sdf_revision, binary_data):
     meas_hdr['average_type'] = average_type_decoder[coded_average_type]
     meas_hdr['average_num'], = struct.unpack('>l', binary_data[30:34])
     meas_hdr['pct_overlap'], = struct.unpack('>f', binary_data[34:38])
-    meas_hdr['meas_title'] = _strip_nonprintable(
-        struct.unpack('>60s', binary_data[38:98])[0])
+    meas_hdr['meas_title'] = _strip_nonprintable(binary_data[38:98])
     meas_hdr['video_bw'], = struct.unpack('>f', binary_data[98:102])
     (meas_hdr['center_freq'], meas_hdr['span_freq'],
         meas_hdr['sweep_freq']) = struct.unpack(
@@ -397,11 +409,11 @@ def read_sdf_file(sdf_filename):
     with open(sdf_filename, 'rb') as sdf_file:
         # Read SDF file_identfication
         file_identifier = sdf_file.read(2)
-        if file_identifier == 'B\x00':
+        if file_identifier == b'B\x00':
             sdf_hdr['valid_file_identifier'] = True
         else:
             # Didn't find a valid file identifer, so bail out
-            sys.exit('Did not find a valid file identifier.')
+            sys.exit('Invalid file identifier: {}'.format(file_identifier))
 
         # Determine record type (short) and record size (long)
         # Every record has these two special fields at the start

tests/test_sdfascii.py

@@ -1,4 +1,11 @@
 # -*- coding: utf-8 -*-
+
+# Try to future proof code so that it's Python 3.x ready
+from __future__ import print_function
+from __future__ import unicode_literals
+from __future__ import division
+from __future__ import absolute_import
+
 import datetime
 import os
 import unittest
@@ -10,22 +17,22 @@
 
 class TestReadingSDFFormat(unittest.TestCase):
 
-    def setUp(self):
-        source_10mVrms_3kHz_directory = os.path.join(
+    def setUp(self):  # noqa
+        source_10mvrms_3khz_directory = os.path.join(
             os.path.dirname(os.path.realpath(__file__)),
             'source_10mVrms_3kHz')
 
-        sdf_file = os.path.join(source_10mVrms_3kHz_directory,
+        sdf_file = os.path.join(source_10mvrms_3khz_directory,
                                 'SDF3KHZ.DAT')
 
-        ascii_ydata_file = os.path.join(source_10mVrms_3kHz_directory,
+        ascii_ydata_file = os.path.join(source_10mvrms_3khz_directory,
                                         'ASCII3KH.TXT')
 
         self.sdf_hdr, self.sdf_data = sdfascii.read_sdf_file(sdf_file)
 
         self.ascii_ydata = np.loadtxt(ascii_ydata_file)
 
-    def tearDown(self):
+    def tearDown(self):  # noqa
         pass
 
     def test_reading_sdf_file_identifier(self):
@@ -477,17 +484,17 @@ def test_ydata(self):
 
 class TestReadingASCIIFormat(unittest.TestCase):
 
-    def setUp(self):
-        source_10mVrms_3kHz_directory = os.path.join(
+    def setUp(self):  # noqa
+        source_10mvrms_3khz_directory = os.path.join(
             os.path.dirname(os.path.realpath(__file__)),
             'source_10mVrms_3kHz')
 
-        ascii_file_basename = os.path.join(source_10mVrms_3kHz_directory,
+        ascii_file_basename = os.path.join(source_10mvrms_3khz_directory,
                                            'ASCII3KH')
 
         self.ascii_data = sdfascii.read_ascii_files(ascii_file_basename)
 
-    def tearDown(self):
+    def tearDown(self):  # noqa
         pass
 
     def test_starting_frequency(self):