是学习PCA特征提取的很好的学习资料，时间序列数据分析中的梅林变换工具，对信号进行频谱分析及滤波，供做算法研究人员参考，是机器学习的例程。-Is a good learning materials to learn PCA feature extraction, Time series data analysis Mellin transform tool, The signal spectral analysis and filtering, Algorithm for researchers to do reference, Machine learning routines.