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What's the difference between Topic and Parameter?

asked 2013-06-24 22:03:06 -0600

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Topic gets data from Publisher. What's the difference between Topic and Parameter?

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answered 2013-06-24 23:12:32 -0600

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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.

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answered 2013-06-24 23:13:55 -0600

davinci gravatar image

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.

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Asked: 2013-06-24 22:03:06 -0600

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Last updated: Jun 24 '13