Publishing .bag file for different nodes

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@galdeano Hey thanks. How would I open (or get access) to the data inside the rosbag file that is recording to `/chatter1` and `/chatter2` whilst it is running though?

I do not understand, why would you access the data on the rosbag file, while you have the real time data published? If you still need to manipulate bag files, use: http://wiki.ros.org/rosbag/Code%20API#cpp_api but as said in the begin of the document: 'Note that the rosbag API's are not thread-safe for reading and writing any given bag file. Users of the APIs must ensure no concurrent input/output operations are performed on different threads.' So you can't read and write at the same time.

@galdeano - Very valid point. I've misunderstood. But, I do not know of a way to subscribe to multiple topics in Python and being able to store this data inside a numpy array? The problem is that, using rosbag it takes both data of the nodes and combines them. I need a way to do this

For numpy use: http://wiki.ros.org/rospy_tutorials/Tutorials/numpy For syncronisation of several topics use: http://wiki.ros.org/message_filters#Policy-Based_Synchronizer_.5BROS_1.1.2B-.5D