| 1. | Bezier , b - spline , and their rational models play an important role in cad / cam systems . but these models show obvious shortcomings , such as no encompassing transcendent ( i . e . , nonalgebraic ) curves , e . g . the circle , the cycloid , the catenary and the hyperbolic helix
B zier ， b -样条以及它们的有理模型在cad cam系统中有着非常重要的地位，但是这些模型也有着明显的缺陷，譬如不能精确表示很多非代数曲线，如圆弧，摆线，悬链线，双曲螺线等 |
