A SEMI-INVERSE ALGORITHM IN APPLICATION OF COMPUTER ALGEBRA

For the purpose of overcoming the difficulty of the so-called ''interm ediate expression swell'' in applying computer algebra, a semi-inverse algorithm is proposed. The or del of seeking solutions for various pr oblems is partly inverted, i. e., the intermediate expressions appeari ng in computation are ''frozen'' in the symbolic form at first, and '' unfrozen'' till the formal expressions of final solutions are found ou t. In this rca!, the overflow due to the shortage of saving space is a voided. The applications of the algorithm in the problems on nonlinear oscillation, dynamical optimization and interfacial solitary waves ar e described, which show the effectiveness of the semi-inverse algorith m.