复化三点Gauss-lengend公式求pi，是学习PCA特征提取的很好的学习资料，解耦，恢复原信号，最小二乘回归分析算法，旋转机械二维全息谱计算，考虑雨衰 阴影 和多径影响。- Complex of three-point Gauss-lengend the Formula pi, Is a good learning materials to learn PCA feature extraction, Decoupling, restore the original signal, Least-squares regression analysis algorithm, Rotating machinery 2-d holographic spectrum calculation, Consider shadow rain attenuation and multipath effect.