n.维数；度数
A set is an ordered set of tuples with the same dimensionality. 集是具有相同维数的有序元组集。
The dimensionality and computation time are not only substantially decreased, but also the accuracy is preserved. 它不仅显著地降低了数学模型的维数和计算时间，而且所得仿真结果能够准确契合精确模型的输出。
