摘要
一般而言,有限差分法求解点源三维地电场正问题所形成的大型稀疏线性方程组Ax=b,直接解法的计算效率极低。本文从系数矩阵A的不完全Cholesky分解及矩阵特征值的特点等角度,说明了不完全Cholesky共轭梯度(ICCG)迭代技术可大大提高电阻率三维正演速度的内在原因。结合矩阵A的稀疏存储模式,使得内存需求也大大减少。
For the large sparse linear equations: A x=b, which are formed from the finite difference method used to solve the 3D forward problem of geoelectrical field,in general,the computational efficiency with direct method is quite slow.In this paper,from the view point of the characteristics of the incomplete Cholesky decomposition of matrixX A and its eigenvalue,the internal cause of greatly increased 3D resistivity forward speed using the incomplete Cholesky conjugate gradient (ICCG) iteration technique is explained .Introducing the rowindexed sparse storage mode to store matrix A, the internal storage demand is greatly decreased.
出处
《煤田地质与勘探》
CAS
CSCD
北大核心
1999年第3期62-66,共5页
Coal Geology & Exploration
关键词
电阻率法勘探
正演
共轭梯度法
迭代技术
电阻率
resistivity prospecting
3D forward
incomplete Cholesky conjugate gradient
sparse storage mode