Function abc::scaling::power_rank [−] [src]

pub fn power_rank(k: f64) -> Box<ScalingFunction>

Chooses solutions according to their rank, raised to a certain power.

This scaling formula was proposed by Yudong Zhang et al for the Fitness-Scaling Chaotic ABC in the 2013 volume of Mathematical Problems in Engineering. Conceptually, it composes the power and rank scaling techniques.

scaled_i = rank_i^k

As with rank scaling, rank_i starts with 1 for the least fit, and continues up to N for the most fit.