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Hello everyone,

reading the recent messages on this list I have a question concerning
the comparison of fitness values: shouldn't they be compared
differently?  An approach to compare for equality would be to check if
they differ at most a very small value or probably even better using
an approach like
http://www.cygnus-software.com/papers/comparingfloats/comparingfloats.htm).

Especially the following methods in SimpleFitness, KozaFitness and
MultiObjectiveFitness could have problems with minor numerical
imprecisions unavoidable when using floating-point numbers:

   public final boolean isIdealFitness()
   public boolean equivalentTo(final Fitness _fitness)
   public boolean betterThan(final Fitness _fitness)

Don't know if this is a real problem and worth fixing given the noise
tolerance of EAs, but certainly an implementation issue.


Best regards
 Torsten