自编的快速小波变换mallat算法，使用‘db1’小波函数，在卷积时使用wkeep命令进行了数据截取。重构信号和原信号比较误差较小。-self fast wavelet transform Mallat algorithm, the use of 'db1' wavelet function, Convolution in the use of wkeep order the interception of data. Reconstruction of the original signal and signal more smaller error.