What's the difference between Topic and Parameter?
Topic gets data from Publisher. What's the difference between Topic and Parameter?
ROS Resources: Documentation | Support | Discussion Forum | Index | Service Status | ros @ Robotics Stack Exchange |
asked 2013-06-24 22:03:06 -0600
This post is a wiki. Anyone with karma >75 is welcome to improve it.
Topic gets data from Publisher. What's the difference between Topic and Parameter?
answered 2013-06-24 23:12:32 -0600
This post is a wiki. Anyone with karma >75 is welcome to improve it.
Parameters are stored centrally on the parameter server and continue to live once whatever set that dies. They usually only contain simple data and can be set during launch. Parameters are usually used as configuration parameters while topics provide streaming changing data.
Technically topics form a direct connection between nodes, while parameters are stored and read from the parameter server.
A topic is intended for a stream of changing data while a parameter is something you set at the begin and don't change that often.
But you probably mean the difference between a publisher and a topic? A topic is a channel on which a publisher publishes data. It is a kind of whiteboard (the topic) on which a person (a publisher) writes things, but multiple people (publishers) can write on the whiteboard. It is also possible that no one is writing on the whiteboard (no publishers) but there are people (subscribers) watching it.
Asked: 2013-06-24 22:03:06 -0600
Seen: 1,571 times
Last updated: Jun 24 '13
basic question in understanding publishing and subscribing
Can I "overload" topic names in ROS? (Different versions by datatype)
Subscribing to the odometry topic
Problem using subscribed motor position topic
publish arrays to a topic on the command line
How to create a global listener for any ROS topic and extract all data from any message?
Diagnostic aggregator not reading messages from new publishers on /diagnostics topic [closed]