目前，pca算法已经广泛应用于各方面，就拿图像处理，经常做的一件事就是当提取的图像特征维度比较高时，为了简化计算量以及储存空间，需要对这些高维数据进行一定程度上的降维，并尽量保证数据的不失真。-Currently, pca algorithm has been widely used in various aspects, Take image processing, often do one thing when the dimensions of the image feature extraction is relatively high, in order to simplify the calculation and storage space, the need for these high-dimensional data to a certain extent dimensionality reduction on, and try to ensure that data is not distorted.