graduation error的用法和样例：
例句
- The principle straightness error of cutting square in work-pieces can be controlled by choosing a suitable pitch diameter of the planetary gear in the machine tools.
选取适当的车头行星轮的分度圆直径，可以有效地控制车方原理的直线度误差。 - The evolutional model and the calculation process are introduced in detail.The flatness error is discussed as an example.
文中以平面度误差为例，详细地介绍了进化模型的建立及计算方法。
