Extracting one of the values from a Message in a Bag file [closed]

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Hey everyone,

Started using ROS a few days ago, nice community you have here!

I'm having troubles with extracting one of the Float values from messages from a Bag file. There is only one topic in the Bag file, and the message contains several Float values. I only need one extracted, and I just don't know how to do it.

I've been searching a lot on answers.ros.org but it seems to be a difficult subject, especially since I'm writing in C++.

Does anyone have an idea?

Any help would be much appreciated!