value is less than a predetermined value the particular parametric representation used may depend on the object to be fit for example a two dimensional parametric curve such as a two dimensional cubic bezier curve whose parameters comprise its four control vertices can be fit to a set of digitized points acquired along a path of a digitizing device such as a computer mouse or a digital pen as a second example a parametric surface patch such as a nurbs surface patch whose parameters comprise a set of control vertices can be fit to a set of three dimensional points acquired with a range scanning device as a third example a two dimensional ellipse whose parameters comprise a center point an orientation a major radius and a minor radius can be fit to a set of two dimensional sampled data points to represent a level set of a bivariate probability density function modeling the data points as a fourth example a set of two dimensional parametric curves can be fit to a medial axis of a closed two dimensional outline as a fifth example a piecewise polynomial bezier surface can be fit to an iso surface of an adaptively sampled distance field there are other examples of parametric representations such as line segments curves.