#### For citation:

Novikov E. A. Algorithm Variable Order, Step and the Configuration Variables for Solving Stiff Problems. *Izvestiya of Saratov University. Mathematics. Mechanics. Informatics*, 2013, vol. 13, iss. 3, pp. 35-43. DOI: 10.18500/1816-9791-2013-13-3-35-43

# Algorithm Variable Order, Step and the Configuration Variables for Solving Stiff Problems

An inequality for stability control of a Ceschino’s scheme of second order of accuracy is constructed. A numerical formula of order one is developed that is based on the stages of the this method and its stability interval is extended to 32. On a base of L-stable (2,1)-scheme and a numerical Ceschino’s formula, an algorithm of alternating structure, in which an efficient numerical formula is chosen on an every step by a stability criterion, is constructed. The algorithm is intended for solving stiff and non-stiff problems. There are shown results of calculations, confirming efficiency of this algorithm.

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