Hrrrrm, I was thinking of the gt operator, sorry to hear it didn't work. You mentioned that it displays '0.00', so I would assume it is an integer. Try comparing against <i>$node.object.data_map.price.data_float</i> instead.
If that doesn't do it, try viewing all of the attributes using <i>|attribute(show)</i>. It may provide some additional information that could lead to an answer.
Alex
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