Home       Trees       Indices       Help   
Package rosbag :: Module bag :: Class Bag
[frames] | no frames]

Class Bag

source code

object --+
         |
        Bag

Bag serialize messages to and from a single file on disk using the bag format.

Instance Methods
 
__init__(self, f, mode='r', compression=Compression.NONE, chunk_threshold=768*1024, allow_unindexed=False, options=None, skip_index=False)
Open a bag file.		 source code
 
__iter__(self) source code
 
__enter__(self) source code
 
__exit__(self, exc_type, exc_value, traceback) source code
 
options(self)
Get the options.		 source code
 
filename(self)
Get the filename.		 source code
 
version(self)
Get the version.		 source code
 
mode(self)
Get the mode.		 source code
 
size(self)
Get the size in bytes.		 source code
generator of tuples of (str, roslib.message.Message, roslib.rostime.Time) [not raw] or (str, (str, str, str, tuple, class), roslib.rostime.Time) [raw]
read_messages(self, topics=None, start_time=None, end_time=None, connection_filter=None, raw=False)
Read messages from the bag, optionally filtered by topic, timestamp and connection details.		 source code
 
flush(self)
Write the open chunk to disk so subsequent reads will read all messages.		 source code
 
write(self, topic, msg, t=None, raw=False)
Write a message to the bag.		 source code
 
reindex(self)
Reindexes the bag file.		 source code
 
close(self)
Close the bag file.		 source code
 
__str__(self)
str(x)		 source code

Inherited from object: __delattr__, __format__, __getattribute__, __hash__, __new__, __reduce__, __reduce_ex__, __repr__, __setattr__, __sizeof__, __subclasshook__

Class Variables
  compression = property(_get_compression, _set_compression)
  chunk_threshold = property(_get_chunk_threshold, _set_chunk_th...
Properties

Inherited from object: __class__

Method Details

__init__(self, f, mode='r', compression=Compression.NONE, chunk_threshold=768*1024, allow_unindexed=False, options=None, skip_index=False)
(Constructor)

source code 

Open a bag file. The mode can be 'r', 'w', or 'a' for reading (default), writing or appending. The file will be created if it doesn't exist when opened for writing or appending; it will be truncated when opened for writing. Simultaneous reading and writing is allowed when in writing or appending mode.

Parameters:
  • f (str or file) - filename of bag to open or a stream to read from
  • mode (str) - mode, either 'r', 'w', or 'a'
  • compression (str) - compression mode, see rosbag.Compression for valid modes
  • chunk_threshold (int) - minimum number of uncompressed bytes per chunk
  • allow_unindexed (bool) - if True, allow opening unindexed bags
  • options (dict) - the bag options (currently: compression and chunk_threshold)
  • skip_index (bool) - if True, don't read the connection index records on open [2.0+]
Raises:
Overrides: object.__init__

options(self)

source code 

Get the options.

Decorators:
  • @property

filename(self)

source code 

Get the filename.

Decorators:
  • @property

version(self)

source code 

Get the version.

Decorators:
  • @property

mode(self)

source code 

Get the mode.

Decorators:
  • @property

size(self)

source code 

Get the size in bytes.

Decorators:
  • @property

read_messages(self, topics=None, start_time=None, end_time=None, connection_filter=None, raw=False)

source code 

Read messages from the bag, optionally filtered by topic, timestamp and connection details.

Parameters:
  • topics (list(str) or str) - list of topics or a single topic [optional]
  • start_time (roslib.rostime.Time) - earliest timestamp of message to return [optional]
  • end_time (roslib.rostime.Time) - latest timestamp of message to return [optional]
  • connection_filter (function taking (topic, datatype, md5sum, msg_def, header) and returning bool) - function to filter connections to include [optional]
  • raw (bool) - if True, then generate tuples of (datatype, (data, md5sum, position), pytype)
Returns: generator of tuples of (str, roslib.message.Message, roslib.rostime.Time) [not raw] or (str, (str, str, str, tuple, class), roslib.rostime.Time) [raw]
generator of (topic, message, timestamp) tuples for each message in the bag file

flush(self)

source code 

Write the open chunk to disk so subsequent reads will read all messages.

Raises:
  • ValueError - if bag is closed

write(self, topic, msg, t=None, raw=False)

source code 

Write a message to the bag.

Parameters:
  • topic (str) - name of topic
  • msg (Message or tuple of raw message data) - message to add to bag, or tuple (if raw)
  • t (roslib.rostime.Time) - ROS time of message publication, if None specifed, use current time [optional]
  • raw (bool) - if True, msg is in raw format, i.e. (msg_type, serialized_bytes, md5sum, pytype)
Raises:
  • ValueError - if arguments are invalid or bag is closed

reindex(self)

source code 

Reindexes the bag file. Yields position of each chunk for progress.

close(self)

source code 

Close the bag file. Closing an already closed bag does nothing.

__str__(self)
(Informal representation operator)

source code 

str(x)

Overrides: object.__str__
(inherited documentation)

Class Variable Details

chunk_threshold

Value:
property(_get_chunk_threshold, _set_chunk_threshold)

   Home       Trees       Indices       Help   
Generated by Epydoc 3.0.1 on Sat Mar 2 13:24:11 2013 http://epydoc.sourceforge.net