GLONASS: added Python bindings for GLONASS message decoder

Added Python bindings for GLONASS message decoder operations.

Author: valeri-atamaniouk

python/setup.py

@@ -2,21 +2,22 @@
 from version import get_git_version
 
 setup_args = dict(
-  name = 'swiftnav',
-  version = get_git_version(),
-  description = 'Python bindings to the libswiftnav library.',
-  license = 'LGPLv3',
-  url = 'http://www.swiftnav.com',
-  author = 'Swift Navigation Inc.',
-  author_email = 'dev@swiftnav.com',
-  maintainer = 'Swift Navigation',
-  maintainer_email = 'dev@swiftnav.com',
-  packages = ['swiftnav'],
+    name='swiftnav',
+    version=get_git_version(),
+    description='Python bindings to the libswiftnav library.',
+    license='LGPLv3',
+    url='http://www.swiftnav.com',
+    author='Swift Navigation Inc.',
+    author_email='dev@swiftnav.com',
+    maintainer='Swift Navigation',
+    maintainer_email='dev@swiftnav.com',
+    packages=['swiftnav'],
 )
 
 if __name__ == "__main__":
   import numpy as np
-  import os, sys
+  import os
+  import sys
   from setuptools import setup, Extension
   try:
     from Cython.Distutils import build_ext
@@ -47,45 +48,47 @@
   include_dirs.append('../include/')
   include_dirs.append('../libfec/include/')
   include_dirs.append('../tests/data/l2cbitstream/')
+
   def make_extension(ext_name):
     ext_path = ext_name.replace('.', os.path.sep) + '.pyx'
     return Extension(
-      ext_name, [ext_path],
-      include_dirs = include_dirs,
-      extra_compile_args = ['-O0', '-g'],
-      extra_link_args = ['-g'],
-      libraries = ['m', 'swiftnav', 'l2cbitstream'],
-      library_dirs = library_dirs,
+        ext_name, [ext_path],
+        include_dirs=include_dirs,
+        extra_compile_args=['-O0', '-g'],
+        extra_link_args=['-g'],
+        libraries=['m', 'swiftnav', 'l2cbitstream'],
+        library_dirs=library_dirs,
     )
   ext_names = [
-    'swiftnav.edc',
-    'swiftnav.signal',
-    'swiftnav.coord_system',
-    'swiftnav.constants',
-    'swiftnav.cnav_msg',
-    'swiftnav.nav_msg',
-    'swiftnav.pvt',
-    'swiftnav.correlate',
-    'swiftnav.track',
-    'swiftnav.almanac',
-    'swiftnav.lambda_',
-    'swiftnav.ephemeris',
-    'swiftnav.linear_algebra',
-    'swiftnav.amb_kf',
-    'swiftnav.time',
-    'swiftnav.observation',
-    'swiftnav.dgnss_management',
-    'swiftnav.ambiguity_test',
-    'swiftnav.baseline',
-    'swiftnav.bits',
-    'swiftnav.filter_utils',
-    'swiftnav.memory_pool',
-    'swiftnav.prns',
-    'swiftnav.sats_management',
-    'swiftnav.iono',
-    'swiftnav.tropo',
-    'swiftnav.set',
-    'swiftnav.bit_sync',
+      'swiftnav.edc',
+      'swiftnav.signal',
+      'swiftnav.coord_system',
+      'swiftnav.constants',
+      'swiftnav.cnav_msg',
+      'swiftnav.nav_msg',
+      'swiftnav.nav_msg_glo',
+      'swiftnav.pvt',
+      'swiftnav.correlate',
+      'swiftnav.track',
+      'swiftnav.almanac',
+      'swiftnav.lambda_',
+      'swiftnav.ephemeris',
+      'swiftnav.linear_algebra',
+      'swiftnav.amb_kf',
+      'swiftnav.time',
+      'swiftnav.observation',
+      'swiftnav.dgnss_management',
+      'swiftnav.ambiguity_test',
+      'swiftnav.baseline',
+      'swiftnav.bits',
+      'swiftnav.filter_utils',
+      'swiftnav.memory_pool',
+      'swiftnav.prns',
+      'swiftnav.sats_management',
+      'swiftnav.iono',
+      'swiftnav.tropo',
+      'swiftnav.set',
+      'swiftnav.bit_sync',
   ]
   extensions = [make_extension(name) for name in ext_names]
   setup_args['ext_modules'] = extensions

python/swiftnav/ephemeris.pyx

@@ -1,4 +1,4 @@
-# Copyright (C) 2015 Swift Navigation Inc.
+# Copyright (C) 2015-2016 Swift Navigation Inc.
 #
 # This source is subject to the license found in the file 'LICENSE' which must
 # be be distributed together with this source. All other rights reserved.

python/swiftnav/nav_msg_glo.pxd

@@ -0,0 +1,49 @@
+# Copyright (C) 2016 Swift Navigation Inc.
+#
+# This source is subject to the license found in the file 'LICENSE' which must
+# be be distributed together with this source. All other rights reserved.
+#
+# THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND,
+# EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED
+# WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A PARTICULAR PURPOSE.
+
+# cython: embedsignature=True
+
+from common cimport *
+from ephemeris cimport *
+from libcpp cimport bool
+from signal cimport gnss_signal_t
+
+cdef extern from "libswiftnav/nav_msg_glo.h":
+  enum:
+    NAV_MSG_GLO_STRING_BITS_LEN
+    GLO_TM
+    GLO_TM_LEN
+
+  ctypedef enum glo_receive_machine:
+    INVALID
+    SYNC_TM
+    GET_DATA_BIT
+
+  ctypedef struct nav_msg_glo_t:
+    u32 string_bits[NAV_MSG_GLO_STRING_BITS_LEN]
+    u16 current_head_bit_index
+    u16 nt
+    u8 next_string_id
+    u8 n4
+    u8 hrs
+    u8 min
+    u8 sec
+    glo_receive_machine state
+    u8 meander_bits_cnt
+    u8 manchester
+    u8 decode_done
+
+  void nav_msg_init_glo(nav_msg_glo_t *n)
+  s8 process_string_glo(nav_msg_glo_t *n, ephemeris_t *e)
+  s8 nav_msg_update_glo(nav_msg_glo_t *n, bool bit_val)
+  double nav_msg_get_tow_glo(nav_msg_glo_t *n)
+  s8 error_detection_glo(nav_msg_glo_t *n)
+
+cdef class NavMsgGlo:
+  cdef nav_msg_glo_t _thisptr

python/swiftnav/nav_msg_glo.pyx

@@ -0,0 +1,108 @@
+# Copyright (C) 2016 Swift Navigation Inc.
+#
+# This source is subject to the license found in the file 'LICENSE' which must
+# be be distributed together with this source. All other rights reserved.
+#
+# THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND,
+# EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED
+# WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A PARTICULAR PURPOSE.
+
+# cython: embedsignature=True
+
+from ephemeris cimport ephemeris_t
+from fmt_utils import fmt_repr
+from time cimport gps_time_t
+from signal cimport gnss_signal_t
+from swiftnav.ephemeris import Ephemeris
+
+
+cdef class NavMsgGlo:
+
+  def __cinit__(self):
+    nav_msg_init_glo(&self._thisptr)
+
+  def __getattr__(self, k):
+    return self._thisptr.get(k)
+
+  def __repr__(self):
+    return fmt_repr(self)
+
+  def to_dict(self):
+    return self._thisptr
+
+  def from_dict(self, d):
+    self._thisptr = d
+
+  def __reduce__(self):
+    return (rebuild_NavMsgGlo, tuple(self.to_dict().items()))
+
+  def updateEphemeris(self, Ephemeris e):
+    return process_string_glo(&self._thisptr, &e._thisptr)
+
+  def update(self, bit_val):
+    return nav_msg_update_glo(&self._thisptr, bit_val)
+
+  def getTow(self):
+    return nav_msg_get_tow_glo(&self._thisptr)
+
+  def detectError(self):
+    return error_detection_glo(&self._thisptr)
+
+  def isDecodeDone(self):
+    return self._thisptr.decode_done != 0
+
+  def __richcmp__(self, other, op):
+    """
+    Weird Cython comparison method. See
+    http://docs.cython.org/src/userguide/special_methods.html.
+    """
+    if op == 2:
+      return self._equal(other)
+    elif op == 3:
+      return not self._equal(other)
+    else:
+      raise NotImplementedError
+
+  def _equal(self, other):
+    """
+    Compare equality between self and another :class:`NavMsg` object.
+
+    Parameters
+    ----------
+    other : :class:`NavMsgGlo` object
+      The :class:`NavMsgGlo` to test equality against.
+
+    Return
+    ------
+    out : bool
+      True if the passed :class:`NavMsg` object is identical.
+
+    """
+    if self.to_dict().keys() != other.to_dict().keys():
+      return False
+
+    for k in self.to_dict().keys():
+      if self.to_dict()[k] != other.to_dict()[k]:
+        return False
+
+    return True
+
+
+def rebuild_NavMsgGlo(*reduced):
+  """
+  Rebuild NavMsg for unpickling.
+
+  Parameters
+  ----------
+  reduced: tuple
+    Tuple of dict of NavMsg nav_msg_t struct fields
+
+  Returns
+  -------
+  out: :class:`NavMsg` instance
+    Rebuilt :class:`NavMsg` instance
+  """
+  nm = NavMsgGlo()
+  nm.from_dict(dict(reduced))
+  return nm
+

python/tests/test_nav_msg_glo.py

@@ -0,0 +1,86 @@
+
+
+from swiftnav.nav_msg_glo import NavMsgGlo
+from swiftnav.ephemeris import Ephemeris
+import numpy
+
+
+def test_imports():
+  """Verify that distributed packages survive setuptools installation.
+
+  """
+  pass
+
+GLO_STRINGS = numpy.asanyarray([[1, 1, 1],  # dummy words
+                                # 01074396999b05c3a850b5
+                                [0x010743, 0x96999b05, 0xc3a850b5],
+                                # 021760a5256204d9c15f66
+                                [0x021760, 0xa5256204, 0xd9c15f66],
+                                # 0380269d60899a6d0e3123
+                                [0x038026, 0x6d0e3123, 0x9d60899a],
+                                # 04865d1cc0000000344918
+                                [0x04865d, 0x00344918, 0x1cc00000],
+                                # 050d100000000340000895
+                                [0x050d10, 0x3, 0x40000895]
+                                ],
+                               dtype=numpy.dtype('>u4'))
+GLO_STRING_BITS = [numpy.unpackbits(s.view(numpy.uint8))[-85:]
+                   for s in GLO_STRINGS]
+
+GLO_TM = numpy.asanyarray([0x3E375096], dtype=numpy.dtype('>u4'))
+GLO_TM_BITS = numpy.unpackbits(GLO_TM.view(numpy.uint8))[-30:]
+
+
+def test_init():
+  '''
+  Object construction test
+  '''
+  msg = NavMsgGlo()
+  assert msg.isDecodeDone() == False
+  assert msg.getTow() == -1.
+
+
+def test_update():
+  '''
+  Object update test
+  '''
+  msg = NavMsgGlo()
+  assert msg.update(0) == -1
+  assert msg.update(0) == -1
+  assert msg.update(0) == -1
+  assert msg.update(1) == -1
+
+  assert msg.isDecodeDone() == False
+  assert msg.getTow() == -1.
+
+
+def test_decode():
+  '''
+  Ephemeris and ToW decoding test.
+  '''
+  msg = NavMsgGlo()
+  n_strings = 0
+  n_tow = 0
+  tow = -1
+  e = Ephemeris()
+  print GLO_STRING_BITS
+  for bit_string in GLO_STRING_BITS:
+    print bit_string
+    for bit in bit_string:
+      assert msg.update(bit ^ 1) == -1
+      if msg.update(bit) == 1:
+        n_strings += 1
+        if msg.updateEphemeris(e) == 1:
+          n_tow += 1
+          tow = msg.getTow()
+
+    # now pass time mark bit by bit to receiver (MSB first), no line code
+    # needed
+    for bit in GLO_TM_BITS:
+      assert msg.update(bit) == -1
+
+  assert n_strings == 5
+  assert n_tow == 1
+  assert isinstance(tow, float)
+  assert tow == 262707.0
+  assert e.toe['tow'] == 262707.0 - 10.