Controlling Radius using attractor points

I have a question. I am using attractor points to manipulate circles (then moving on to polygons) but I need to control the radius of the circles. I want to say things like: If the radius of the circle is less than .124 inch or greater than .126 inch then the radius is equal to .125 inch

I have six pre-determined sizes that will give me the range of radius sizes I need to ultimately fabricate the pattern. I am just not sure how to control those sizes. Any help would be great. Thanks