An Optimized Modified Walk on Equations Monte Carlo Algorithm for Large Sparse Linear Systems
Venelin Todorov, Fatima Sapundzhi, Metodi Popstoilov
DOI: http://dx.doi.org/10.15439/2026F9246
Citation: Venelin Todorov, Fatima Sapundzhi, Metodi Popstoilov (2026). An Optimized Modified Walk on Equations Monte Carlo Algorithm for Large Sparse Linear Systems. In M. Bolanowski, M. Ganzha, M. Grzegorowski, L. Maciaszek, M. Paprzycki, A. Paszkiewicz, D. Ślęzak (eds), Proceedings of the 21st Conference on Computer Science and Intelligence Systems (FedCSIS). ACSIS, Vol. 47, pages 435–442.
Abstract. This paper investigates stochastic Walk on Equations (WE) methods for the numerical solution of linear algebraic systems and proposes an optimized modified WE algorithm aimed at large sparse matrices. Building on the classical WE Monte Carlo framework and its more recent modified version, we reformulate the main computational procedures, compare their algorithmic structure, and discuss their suitability for large-scale problems. To the best of our knowledge, this is the first study in the present setting that explicitly directs the WE methodology toward large sparse linear systems and interprets the modified construction as the basis for a new optimized stochastic solver. The paper considers the classical WE method, the modified WE method, and standard stationary iterative schemes, namely Jacobi and Gauss--Seidel. Their behavior is examined through numerical experiments for systems of dimensions n = 500 and n = 1000, where the relative error is analyzed as a function of the iteration number. The obtained results show that the modified WE algorithm consistently outperforms the classical WE approach and both deterministic benchmarks in terms of convergence speed and final accuracy. In particular, the new method exhibits a significantly faster decay of the relative error and preserves its favorable behavior as the dimension increases. These findings indicate that the modified WE framework is not merely a reformulation of the original stochastic scheme, but a practically more effective Monte Carlo strategy. The reported results also suggest that it provides a promising foundation for the development of optimized algorithms for large sparse linear systems, where efficiency, scalability, and controlled trajectory behavior are of primary importance.
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