Surface fitting and a new direct method for solving block band linear system

Empirical values loaded by accidental errors of normal law are given in the grid points of a rectangular domain. The most probable true values are det ermined by minimizing the sum of the r(th) divided differences and the diff erences between the empirical and the smoothed values simultaneously. Choos ing appropriate weights the quality of smoothing can be controlled. The coe fficients of the linear algebraic equation system (L.E.S.) to be served can be arranged in a block band matrix, A new direct method for solving the L. E.S. is presented needing comparatively small storing capacity and number o f operations. (C) 1999 Elsevier Science Ltd. All rights reserved.