Source Code for Module rospy.numpy_msg

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 34   
 35  """ 
 36  Support for using numpy with rospy messages. 
 37   
 38  For tutorials, see U{http://www.ros.org/wiki/rospy_tutorials/Tutorials/numpy} 
 39   
 40  Listener example:: 
 41      from rospy.numpy_msg import numpy_msg 
 42   
 43      rospy.init_node('mynode') 
 44      rospy.Subscriber("mytopic", numpy_msg(TopicType) 
 45   
 46  Publisher example:: 
 47   
 48      from rospy.numpy_msg import numpy_msg 
 49      import numpy 
 50       
 51      pub = rospy.Publisher('mytopic', numpy_msg(TopicType), queue_size=10) 
 52      rospy.init_node('mynode') 
 53      a = numpy.array([1.0, 2.1, 3.2, 4.3, 5.4, 6.5], dtype=numpy.float32) 
 54      pub.publish(a) 
 55  """ 
 56   
 57  import numpy 
 58   
 59  # TODO: we will need to generate a new type structure with 
 60  # little-endian specified and then pass that type structure into the 
 61  # *_numpy calls. 
 62   
 63 -def _serialize_numpy(self, buff): 
 64      """ 
 65      wrapper for factory-generated class that passes numpy module into serialize 
 66      """ 
 67      # pass in numpy module reference to prevent import in auto-generated code 
 68      return self.serialize_numpy(buff, numpy) 
 69   
 70 -def _deserialize_numpy(self, str): 
 71      """ 
 72      wrapper for factory-generated class that passes numpy module into deserialize     
 73      """ 
 74      # pass in numpy module reference to prevent import in auto-generated code 
 75      return self.deserialize_numpy(str, numpy) 
 76       
 77  _numpy_msg_types = {} 
 78  ## Use this function to generate message instances using numpy array 
 79  ## types for numerical arrays.  
 80  ## @msg_type Message class: call this functioning on the message type that you pass 
 81  ## into a Publisher or Subscriber call.  
 82  ## @returns Message class 
 83 -def numpy_msg(msg_type): 
 84      if msg_type in _numpy_msg_types: 
 85          return _numpy_msg_types[msg_type] 
 86   
 87      classdict = { '__slots__': msg_type.__slots__, '_slot_types': msg_type._slot_types, 
 88                    '_md5sum': msg_type._md5sum, '_type': msg_type._type, 
 89                    '_has_header': msg_type._has_header, '_full_text': msg_type._full_text, 
 90                    'serialize': _serialize_numpy, 'deserialize': _deserialize_numpy, 
 91                    'serialize_numpy': msg_type.serialize_numpy, 
 92                    'deserialize_numpy': msg_type.deserialize_numpy 
 93                    } 
 94   
 95      # create the numpy message type 
 96      msg_type_name = "Numpy_%s"%msg_type._type.replace('/', '__') 
 97      numpy_type = type(msg_type_name,(msg_type,),classdict) 
 98      _numpy_msg_types[msg_type] = numpy_type 
 99      return numpy_type 
100