使用 Golang 在遗传算法中选择轮盘赌

Question

我正在为遗传算法构建一个模拟轮盘选择函数。首先，我会想加起来sum的fitnessScore主功能。加起来后，fitnessScore我想sum使用math/randGo 中的包随机化一个值。在这种情况下我应该如何使用 rand 包如何修复spin_wheel := rand.sum以随机化一个值？package mainimport(    "fmt"    "time"    "math/rand")func rouletteWheel(fitnessScore []float64) []float64{    sum := 0.0    for i := 0; i < len(fitnessScore); i++ {        sum += fitnessScore[i]    }    rand.Seed(time.Now().UnixNano())    spin_wheel := rand.sum    partial_sum := 0.0    for i := 0; i < len(fitnessScore); i++{        partial_sum += fitnessScore[i]        if(partial_sum >= spin_wheel){            return fitnessScore        }    }    return fitnessScore}func main(){    fitnessScore := []float64{0.1, 0.2, 0.3, 0.4}    fmt.Println(rouletteWheel(fitnessScore))}

Answer 1

例如，

package main

import (

    "fmt"

    "math/rand"

    "time"

)

// Returns the selected weight based on the weights(probabilities)

// Fitness proportionate selection:

// https://en.wikipedia.org/wiki/Fitness_proportionate_selection

func rouletteSelect(weights []float64) float64 {

    // calculate the total weights

    sum := 0.0

    for _, weight := range weights {

        sum += weight

    }

    // get a random value

    value := rand.Float64() * sum

    // locate the random value based on the weights

    for _, weight := range weights {

        value -= weight

        if value <= 0 {

            return weight

        }

    }

    // only when rounding errors occur

    return weights[len(weights)-1]

}

func main() {

    rand.Seed(time.Now().UnixNano())

    weights := []float64{0.1, 0.2, 0.3, 0.4}

    fmt.Println(rouletteSelect(weights))

}