说明：  该python代码以一个巨大的矩阵（例如3D重力核）作为输入，然后执行小波压缩以提高效率...，
(This python code takes a huge matrix (e.g. 3D gravity kernel) as an input and then performs wavelet compression to improve the efficiency of matrix multiplication. Note that the multiplication of two matrices in the wavelet domain is equal to the multiplication in the real domain. This wavelet compression was introduced by Li and Oldenburg,)