The use of gradient methods to solve sparse nonsymmetric systems of algebraic equations

Abstract

The application of the iterative gradient method ORTHOMIN to solve difference equations with a non-self-adjoint finite-difference operator is considered. The iterations are experimentally shown to converge at the rate O(N 1 2 ) , where N is the total number of equations. The program realizing the method requires only the structure of the matrix and the values of the nonzero matrix elements as input.