中文说明：这个是关于pca-威胁估计的程序，包括有如何求综合主成分指标，求分子矩阵，求分母矩阵对应的前一项，等等。供大家进行学习和参考，谢谢。
English Description：
This is a threat assessment of PCA procedures, including how to seek comprehensive principal component index, matrix molecules, for the denominator matrix corresponding to the last, and so on. For everyone to learn and reference, thank you.