Abstract. We solve curve fitting problems using Particle Swarm Optimization (PSO). PSO is used to optimize control points and weights of two conic curves to a set of data points. PSO is used to find the best middle control point and weight for both conic curves to provide piecewise conics that preserve G^1 continuity. We present numerical result using parameter changes in PSO scheme. We obtain appropriate parameter values of PSO that provide best error and fastest time to solve curve fitting problem.Keywords: Curve fitting, particle swarm optimization, parameter tuning.
IntroductionIt is generally known that there is a trade-off between exact methods and soft computing (heuristic) methods. Exact methods guarantee accurate/optimal solutions but require a relatively long computational time. Soft computing methods, on the other hand, do not guarantee optimal solution but require a relatively short computational time. For most medical imaging purposes, which often require constructing empirical models which preserve the shape and match data samples or approximate data samples and unknown entity at intermediate location, short computational time is preferred. Thus, we intend to explore the ability of Particle Swarm Optimization (PSO) methods in curve fitting for this purpose. PSO is an optimization technique proposed by Kennedy and Eberhart by means of particle swarm [9]. PSO incorporates swarming behaviours observed in flocks of birds, school of fish, swarm of bees and even social behaviour, from where the idea emerged. PSO is a population-based optimization tool, which could be implemented and applied easily to solve various function optimization problems, or problems that can be transformed to function optimization problems. As an algorithm, its fast convergence compares favourably with many global optimization algorithms like Genetic Algorithm [3], Simulated Annealing [6] and other global optimization algorithms. To apply PSO successfully, one of the key issues is finding ways to map problem solution into PSO article, which directly affects its feasibility and performance.