Pull the hand guards and look underneath. If the barrel is floated, there will be a tube in between the hand guards and barrel.
An easier way to see the difference is to just look at the front sling swivel, if it connected to the front sight, instead of a clip at the end of the hand guard tube, the barrel is not floated.
The hand guards on DCM floated barrels and non floated barrels are the same, it's just the floated barrel tube requires the guards to be modified to fit over the tube, verses just attaching to the front sight clip.
Also, there is a tube system that replaces the stock hand guards completely. If your hand guard is a round tube, the barrel is floated (no pressure to the end of the barrel from the front gripping/slinging system).