Basics

Contents

findros(package_name, resource_name)

Return filesystem path to resource in a package, such as a rosparam file or a roslaunch file. e.g.

In [1]: findros('rosparam', 'example.yaml')
Out[1]: '/home/kwc/ros/tools/rosparam/example.yaml'

ok()

Return True if it is okay to keep executing. If False, calling code should terminate, e.g.
```
while ok():
  do stuff...
```

info(obj)

Get information about a resource, e.g. a node, topic, or service:
```
info(nodes.rosout)
```

kill(obj)

rostype(obj)

Get the type of an object, e.g. the message class for a topic:

In [1]: rostype(topics.chatter)
Out[1]: <class 'std_msgs.msg._String.String'>

rostype(obj, type)

Set the type of an object, e.g. the message class for a topic. You may need to use this if publishing to a topic where the type cannot be inferred:
```
In [1]: rostype(topics.echo, msg.std_msgs.String)
In [2]: topics.echo('hello world')
```

loginfo(msg, *args), logerr(msg, *args), logdebug(msg, *args), logfatal(msg, *args)

Time and Duration

now()

Time

Duration

Rate(hz)

sleep(duration)

Sleep for the specified duration (Duration or float seconds). Alias for rospy.sleep()

Header

autoheader(frame_id='base_link')

Generate a new Header with the timestamp set to the current time and the frame_id set to base_link. Optionally, you can pass in your own frame_id.