Hi Cedric, I don't know if what you say applies here. If I understood you well when you mention 'testing software', that would be achieved using 'rosbag play'. If you are using 'rostopic echo' you'll just get a bunch of data printed on screen (or to a text file). Miguel. 2010/6/9 Cedric Pradalier > On 06/09/2010 04:31 PM, Jeremy Leibs wrote: > > Agreed. I was also surprised to find it didn't print bag time. I > > created ticket: https://code.ros.org/trac/ros/ticket/2780 to track > > this issue. > > > > I actually implemented a playback functionality for another middleware > some time ago, and I had put that as an option. > In some context, one would want to have the time at which the data was > recorded (for plotting for instance). > On the other hand, if you test some software, then it's better to put > the writing time, to have a feeling of real-time. > > Then I also had an option for time scaling (fast-forward or > slow-motion). Then again, the choice of old time-stamp, write time-stamp > becomes tricky, especially if you introduce a pause mechanism in the > playback. > > Even without the special features above, I think both type of timestamp > are sometimes useful, and only a command-line option can select between > them. > > HTH > > > On Wed, Jun 9, 2010 at 2:14 AM, Miguel Prada > wrote: > > > >> Hi Jeremy, > >> > >> Thanks for the tip. That's exactly what I've been doing after writing to > the list and it works great. > >> > >> However, shouldn't rostopic output the bagfile's timestamps when echoing > from a bagfile? I find it much more reasonable than having to > programatically read the data using python to achieve this result. Am I > missing some important reason for rostopic echo to behave this way? > >> > >> Miguel. > >> > >> El 09/06/2010, a las 10:33, Jeremy Leibs escribió: > >> > >> > >>> Assuming you are still using boxturtle, rosrecord has a rosrecord.py > >>> programmatic API > >>> > >>> Take a look at: > >>> > >>> http://www.ros.org/wiki/rosrecord#rosrecord.py > >>> > >>> It should be fairly straight forward to write a small program which > >>> opens the bag and prints exactly what you want. > >>> > >>> On Wed, Jun 9, 2010 at 1:29 AM, Miguel Prada > wrote: > >>> > >>>> Hi, > >>>> > >>>> I want to manipulate some data from a bag file with a spreadsheet. I'm > exporting from the bag to CSV using 'rostopic echo -p -b BAGFILE TOPIC>> > file.csv' but I just realised that the time field you get from doing that > is the time corresponding to when rostopic is run, not the time stored in > the bag file. That means that if I use this method to output messages in one > topic and then repeat for another topic (e.g. controller commands and robot > positions) the time fields on both CSV files are of no use at all to merge > the data in those two files. > >>>> > >>>> I tried using 'rostopic echo -p -b BAGFILE -a>> file.csv' to print > all topics at once, but the output is quite messed up and doesn't clearly > state which data corresponds to which topic. > >>>> > >>>> Does anyone have any suggestion on how should I proceed with this? > >>>> > >>>> Miguel. > >>>> > >>>> _______________________________________________ > >>>> ros-users mailing list > >>>> ros-users@code.ros.org > >>>> https://code.ros.org/mailman/listinfo/ros-users > >>>> > >>>> > >>> _______________________________________________ > >>> ros-users mailing list > >>> ros-users@code.ros.org > >>> https://code.ros.org/mailman/listinfo/ros-users > >>> > >> _______________________________________________ > >> ros-users mailing list > >> ros-users@code.ros.org > >> https://code.ros.org/mailman/listinfo/ros-users > >> > >> > > _______________________________________________ > > ros-users mailing list > > ros-users@code.ros.org > > https://code.ros.org/mailman/listinfo/ros-users > > > > > -- > Dr. Cedric Pradalier > http://www.asl.ethz.ch/people/cedricp > > _______________________________________________ > ros-users mailing list > ros-users@code.ros.org > https://code.ros.org/mailman/listinfo/ros-users >