CutoffRadius is an option to ConnectionList. The value Infinity is default. If the distance between two point is larger than 2 times the CutoffRadius value, the two points are not connected. Remember, that the DistanceMatrix function represents the squared distances, so the matrix values are compared to 4 times the CutoffRadius value squared. CutoffRadius is also an option to InterpolationCoefficients and to Interpolation when Method"ObtuseAngle" is specified. The interpolated value is not affected by the function value in control points that are more distant than the CutoffRadius value.