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first of all, thank you for answering.

i did try it all you said even before posting the question.

still haven't found any solution to my problem with reading that tf. Tf with command tf tf_echo /map /odom looks alright: "Traslation: (-0.336 , 0.318, 0.000)" , and still I can't get it right.

lets add things up on my question:

• rosbag play --clock basic_localization_stage.bag is command I start the .bag

• rosrun gmapping slam_gmapping scan:=base_scan

• rosparam set /use_sim_time true in CLI

• then start my node to read tf

and this is what i get: "Lookup would require extrapolation into the past. Requested the time 38.9583

but the earliest data is at time 39.1473, when looking up transform

from frame /map to /odom"

I place new code to it: (now it has waiting for tf, and still wrong one)

tf::TransformListener listener;
ros::Rate rate(1.0);
while (nh.ok()){
    tf::StampedTransform tfTransform;
    try{
        ros::Time now = ros::Time::now();
        listener.waitForTransform("/odom", "/map",
                                  now, ros::Duration(5.0));
        listener.lookupTransform("/odom", "/map",
                                 now, tfTransform);
    }
    catch(tf::TransformException &exception) { 
        ROS_ERROR("%s", exception.what());
    }

    ROS_INFO("%f %f %f", tfTransform.getOrigin().x(), tfTransform.getOrigin().y(), tfTransform.getOrigin().z());
    rate.sleep();

}