How to find out intensity of a point cloud at a particluar point in the Pointcloud?

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Hello everyone,

I have a bag file that has recorded 25s of point cloud data. I want to find the intensity values at two different points in the point cloud. While searching, I found this answer for one of the questions asked on ROS answers.

Can I use the method mentioned from the above link, e.g rostopic echo /clicked_point to get the x,y,z points from rviz and then use this in my code to find the intensity at that particular point? Will this method work?

If not, is there another way to get intensity values at a particular point in the Point cloud?

Thank you in Advance.