datum transformation

• 坐标转换

datum transformation的用法和样例：

例句

1. The unitary iris image is carried out through the transformation from Cartesian coordinates to polar coordinates.
   然后采用极坐标转换对虹膜图像进行归一化。
2. This paper presents calculation method and coordinate transformation relation in detail, which can be used in similar project design directly and reduce design work greatly.
   对计算方法和坐标转换关系作了详细介绍，可直接运用于类似工程设计，从而使设计工作量大为减少。