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Hi,
In ros2 programming, sometimes I see code like this:
nh->create_publisher<sensor_msgs::msg::PointCloud2>("/ndt_map", 1000);
the topic name has a prefix of "/";
sometimes I see code like this:
nh->create_subscription<sensor_msgs::msg::PointCloud2>("points_raw",
the topic name has no "/".
What's the difference?
The difference appear when using namespaces. If I am using a node with namespace "robot1" and subscribe to the topic "/my_topic" it will subscribe to this topic. But if I subscribe to the topic "my_topic" the node will subscribe to the topic "/robot1/my_topic".
You can add namespaces when launch a node from a launch file by using the group tag for example
Asked: 2023-08-07 20:12:24 -0500
Seen: 80 times
Last updated: Aug 08 '23
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