ISUDS(ID:7491/)

Interactive simulation language 

for Iterative Scheme Using a Direct Solution

Interactive simulation language
References:
  • [Westinghouse Electric Corp., Pittsburgh, Pa.] ISUDS - Iterative Scheme Using a Direct Solution M69-10297 view details Abstract: When solving a system of simultaneous equations on a computer, the accuracy of the solution decreases as the order of the system increases. ISUDS finds a solution to the system of equations and increases the accuracy of the solution by a direct method of computation. Using this method, double precision accuracy is obtained while using a single precision coefficient matrix. The equations are written in matrix form as AX = B, where A is square, non-singular matrix, X is a vector and B is a vector. A solution for X is obtained and substituted in the system. The right-hand members of a new set of equations are the residuals obtained from the first solution. Using the residuals as right-hand members the system of equations are solved again. The first solution (X1), satisfies the equations with right-hand members equal to vector B minus the residuals R. The second solution (X2) satisfies the same system with the residuals as right-hand members. The method presented is a one step improvement procedure however, by redefining X1 as X1 a X2 (the improved solution, any desired accuracy could be obtained. The highest order problem solved by the program is 170.

          in Computer Program Abstracts Cumulative Issue July 15, 1969 -- July 15, 1971 view details