说明：  一种用于非线性降维的流形学习算法，主要是先考虑用每一点处的局部切空间表示该点处的几何特征，然后都局部切空间进行排列
(A manifold learning algorithm for nonlinear dimension reduction, mainly consider to use every bit of the local tangent space representation of geometric feature at that point, then the local tangent space alignment )