Each xy-pair node defines a single point on the fuzzy curve. Because the data feeding each xy-pair nodes can change, the shape of the fuzzy curve can change dynamically. In other words, you can build a fuzzy curve that changes shape to reflect changing conditions.
The fuxxy curve's data link must be a numeric value. Otherwise the fuzzy curve will evaluate to undetermined, the same as if the data link had no data.
At runtime each xy-pair is evaluated to determine their current values.
The nodes are then used to construct a fuzzy curve in memory where each xy-pair's current values define the transition points on the fuzzy curve.
The data link's value defines the x position on the fuzzy curve and the corresponding y value from the curve is returned.