Add a small bias to differentiate composition with similar fitness

JuliaConstraints · Jul 15, 2021 · 26d144d · 26d144d
1 parent d7bb0b8
commit 26d144d
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diff --git a/src/genetic.jl b/src/genetic.jl
@@ -22,7 +22,7 @@ end
 Optimize and set the weigths of an ICN with a given set of configuration `X` and solutions `X_sols`.
 """
 function _optimize!(icn, X, X_sols, dom_size, param=nothing; metric=hamming, pop_size=200, iter=100)
-    fitness = weigths -> loss(X, X_sols, icn, weigths, metric, dom_size, param)
+    fitness = w -> loss(X, X_sols, icn, w, metric, dom_size, param) + weigths_bias(w)
 
     _icn_ga = GA(
         populationSize=pop_size,

diff --git a/src/metrics.jl b/src/metrics.jl
@@ -14,3 +14,8 @@ minkowski(x, X, p) = mapreduce(y -> sum(abs(x .- y)^p)^(1/p), min, X; init = sum
 """
 manhattan(x, X) = minkowski(x, X, 1)
 
+"""
+    weigths_bias(x)
+A metric that bias `x` towards operations with a lower bit. Do not affect the main metric.
+"""
+weigths_bias(x) = sum(p -> p[1] * log2(1. + p[2]), enumerate(x)) / length(x)^4