tdenewiler / node_example Goto Github PK

Hello tdenewiler:
when I follow your step on ROS tutorial about node_example package, after executing cmake .there is a warning, and I didn't care about it . At last rosmakedidn't complete .So I didn't get the last bin directory.I will appreciate your help if could reply as soon as possible.Below is the snapshot about the warning

Hi,

I tried to reproduce your example but the travis console log shows that the code coverage is now working: "Error: No coverage report found". The command returns 0 so the build passes but the coverage actually doesn't work.

Do you have any ideas ?

Hi Thomas,

I'm trying to learn from your package, and I had a problem when running it.

So, if I do roslaunch node_example node_example.launch there is no problem, the package runs perfectly.

And if I run individual nodes after doing roscore, rosrun node_example talker, rosrun node_example listener, and rosrun node_example pylistener.py have no problem.

However, if I run rosrun node_example pytalker.py, I always get the following error msg:

$ rosrun node_example pytalker.py
Traceback (most recent call last):
File "/home/zongyao/zongyao_ws/ros_ws/src/node_example/src/pytalker.py", line 79, in
NodeExample()
File "/home/zongyao/zongyao_ws/ros_ws/src/node_example/src/pytalker.py", line 25, in init
rospy.loginfo('rate = %f', rate)
File "/usr/lib/python2.7/logging/init.py", line 1167, in info
self._log(INFO, msg, args, **kwargs)
File "/usr/lib/python2.7/logging/init.py", line 1286, in _log
self.handle(record)
File "/usr/lib/python2.7/logging/init.py", line 1296, in handle
self.callHandlers(record)
File "/usr/lib/python2.7/logging/init.py", line 1336, in callHandlers
hdlr.handle(record)
File "/usr/lib/python2.7/logging/init.py", line 759, in handle
self.emit(record)
File "/opt/ros/kinetic/lib/python2.7/dist-packages/rosgraph/roslogging.py", line 176, in emit
record_message = _defaultFormatter.format(record)
File "/usr/lib/python2.7/logging/init.py", line 465, in format
record.message = record.getMessage()
File "/usr/lib/python2.7/logging/init.py", line 329, in getMessage
msg = msg % self.args
TypeError: float argument required, not str

So I was wondering where did I do wrong and if you could help me out?

Thank you very much!

Sincerely,
Zongyao

Hi,
I'm a new comer to ROS and trying to use the node_example package to get some basic ideas about ros nodes. I'm confused about when to use ros::init to initialize a ros node, as I couldn't find the initialization process in talker.cpp and listener.cpp. Although the nodes talker and listener have been initialized in talker_node.cpp and listener_node.cpp respectively, these two cpp files have not been launched by any launch files. It would be appreciated if anyone could help me with this misunderstanding. It has confused me for several days.
Also, should the node name in the function ros::init(argc, argv, "my_node_name") be the same as the name of the executable file which defines the node?

The rospy talker node crashes when the rate parameter is set to anything other than 1 and running:

roslaunch node_example node_example.launch

The error is:

Exception in thread Thread-4:
Traceback (most recent call last):
  File "/usr/lib/python2.7/threading.py", line 801, in __bootstrap_inner
    self.run()
  File "/opt/ros/kinetic/lib/python2.7/dist-packages/rospy/timer.py", line 221, in run
    r = Rate(1.0 / self._period.to_sec(), reset=self._reset)
ZeroDivisionError: float division by zero

This should be fixed.