The Location of Singular and Inflection Points for Planar Cubic B-Spline Curve

Using vectors between control points(ai=Pi 1-Pi),parameters λ and μ（such that aj 1=λai μai 2)ae used to study the shape classification of planar parametric cubic B-spline curves.The regiosn of λμ space corresponding to different geometric features on the curves are investigated.These results are useful for curve design.