curve surface by controlling the attractor points

 I can do the attractor in this way. The attract point controlling the scale of the circle line. 

I want to do this kind of curve surface but using with the attract points. like this diagram.

There some some attract points on same floor plan. But the points will have different level of the effect to the points. Eg, may be one point is less affect to the surface. Also, the surface closer to the point, the closer to the ground. 

How can i do it?

This is my first time by using grasshopper.

Hoping someone can help me. Thanks a lot!!!