今天是《雷达哔哔哔》的第二篇,依然关注架构,Blip是Architectural fitness function。 ? 解决方案: 通过识别架构演进度量指标,编写Architectural fitness function(适应度函数),以此量化及可视化系统架构演进效果,并通过持续反馈不断调整技术架构演进方向,避免架构演进脱离初始目标 解读: Architectural fitness function(适应度函数)借鉴自进化计算,被用来衡量方案对满足目标的适合度。 记住,如果你无法为系统演进、架构升级优化定义出度量的Metrics,并通过Fitness Function写一个测试来驱动和可视化你的架构演进成果。
total_fitness = np.sum(fitness) # 计算选择概率 selection_probs = fitness / total_fitness total_fitness = np.sum(fitness) selection_probs = fitness / total_fitness cumulative_probs if fitness[best_idx] > self.best_fitness: self.best_fitness = fitness[best_idx] : """轮盘赌选择操作""" total_fitness = np.sum(fitness) probs = fitness / total_fitness if fitness[best_idx] > self.best_fitness: self.best_fitness = fitness[best_idx]
= pbest_fitness.min() # 记录算法迭代效果 fitness_value_lst.append(gbest_fitness) # 迭代过程 for = fitness_func(distance_matrix, x_i) fitness_old = pbest_fitness[j] if fitness_new < fitness_old: pbest_fitness[j] = fitness_new pbest[j] = x_i gbest_fitness_new = pbest_fitness.min() gbest_new = pbest[pbest_fitness.argmin()] if gbest_fitness_new < gbest_fitness: gbest_fitness = gbest_fitness_new
这一迭代过程的伪代码: START Generate the initial population Compute fitness REPEAT Selection Crossover = 0; } //Calculate fitness public void calcFitness() { fitness = 0; for(int i = 0;i < 5; i ++) { if( <= individuals[i].fitness) { maxFit = i; } } fittest = individuals[maxFit].fitness; return individuals > individuals[maxFit1].fitness) { maxFit2 = maxFit1; maxFit1 = i; } else if(individuals[i].fitness > >= individuals[i].fitness) { minFit = i; } } return minFit; } //Calculate fitness of each individual
假设个体(individual)用\(h_i\)表示,该个体的适应度(fitness)为\(Fitness(h_i)\),被选择的概率为\(P(h_i)\)。 Fitness Selection 该方法也叫 Roulette Wheel Selection(轮盘赌博选择),种群中的个体被选中的概率与个体相应的适应度函数的值成正比。 \[P(h_i)=\frac{Fitness(h_i)}{\sum_{j=1}^N Fitness(h_j)}\] II. 以预设的概率\(p\)从步骤一中选择的\(K\)个individuals的fitness最高的个体 以概率\((1-p)p\)从步骤一中选择的\(K\)个individuals的fitness第二的个体 以概率\((1-p)^2p\)从步骤一中选择的\(K\)个individuals的fitness第二的个体 ...同理 III.
= f(transform_population) return fitness_score - fitness_score.min() # 在select函数中按照个体的适应度进行抽样的的时候 ,抽样概率值必须是非负的 # 对种群按照其适应度进行采样,这样适应度高的个体就会以更高的概率被选择 def select(self, population, fitness_score ): fitness_score = fitness_score + e- # 下一步抽样的过程中用到了除法,出现除法就要考虑到分母为0的特殊情况 idx = np.random.choice (np.arange(self.n_population), size=self.n_population, replace=True, p=fitness_score/fitness_score.sum = self.fitness(population) best_person = population[np.argmax(fitness_score)]
=NectarSource[i].fitness; EmployedBee[i].rfitness=NectarSource[i].rfitness; EmployedBee[i].trail= [i].trail; } /*****最优蜜源的初始化*****/ BestSource.trueFit=NectarSource[0].trueFit; BestSource.fitness= NectarSource[0].fitness; BestSource.rfitness=NectarSource[0].rfitness; BestSource.trail=NectarSource ()//计算轮盘赌的选择概率 { int i; double maxfit; maxfit=NectarSource[0].fitness; for (i=1;i<FoodNumber;i++) { if (NectarSource[i].fitness>maxfit) maxfit=NectarSource[i].fitness; } for (i=0;i<FoodNumber
(route)) fitness = 1 - fitness/np.sum(fitness) # 归一化后取反 return np.array(fitness) def select(self,pop_routes): fitness = self.get_fitness(pop_routes) #轮盘赌的形式进行选择,适应度高的被选中的概率就大 def get_fitness(self,pop_routes): fitness = [] for route in pop_routes: fitness.append (self.get_route_distance(route)) fitness = 1 - fitness/np.sum(fitness) # 归一化后取反 return def select(self,pop_routes): fitness = self.get_fitness(pop_routes) #轮盘赌的形式进行选择,适应度高的被选中的概率就大
基因评价函数 def evaluate_fitness(chrom: list) -> int: """ Evaluate the fitness of a solution using ()) """ population_fitness_values = [] for chrom in population: # 遍历种群中每一个成员的基因,得到其基因”评分 “ population_fitness_values.append(evaluate_fitness(chrom)) sorted_population = [x for _ ) best_fitness = evaluate_fitness(best_chrom) print('Best Solution: ', best_chrom) print('Best Fitness : ', best_fitness) 最终解 对于该问题,最终的解为选择物品1、3、4装入背包,总重量为75(满足小于80的需求),总价值为45。
); %-------------------------------------------------------------------------- best=struct('fitness ,X]=FitnessFunction(binary,lenchrom); % 使用目标函数计算适应度 %% 记录最佳个体到best [best.fitness bestindex] =max(fitness); % 找出最大值 best.binary=binary(bestindex,:); best.chrom=chrom([2*bestindex-1:2*bestindex ]=max(fitness); % 找到最佳值 % 记录最佳个体到best if newbestfitness>best.fitness best.fitness= (i)>=best.fitness) delta=0.01*pi; if A*B>0 s=-1;
(j) = fun(pop_x(:,j)); else fitness_lbest(j) = 500; end else fitness_lbest(j) = 500 ; end end %% 初始化全局极值 popbest = pop_x(:,1); fitness_popbest = fitness_lbest(1); for j = 2:popsize if fitness_lbest(j) < fitness_popbest fitness_popbest = fitness_lbest(j); popbest else fitness_pop(j) = 500; end else fitness_pop(j) = 500; end ) < fitness_lbest(j) lbest(:,j) = pop_x(:,j); fitness_lbest(j) = fitness_pop(
= self.fitness class PSO: def __init__(self, x_min, x_max, y_min, y_max, num_particles, max_iterations for particle in self.particles: if particle.fitness < particle.best_fitness: = particle.fitness if particle.fitness < self.best_global_fitness: self.best_global_y = particle.y self.best_global_fitness = particle.fitness for particle in self.particles: particle.velocity_x
= fitness_func(X) g_fitness = p_fitness.min() fitness_val_list.append(g_fitness) # 初始化的个体最优位置和种群最优位置 if p_fitness[j] > p_fitness2[j]: pbest[j] = X[j] p_fitness[j] = p_fitness2 [j] # 更新群体的最优位置 if g_fitness > g_fitness2: gbest = X[p_fitness2. argmin()] g_fitness = g_fitness2 # 记录最优迭代记录 fitness_val_list.append (g_fitness) i += 1 # 输出迭代结果 print("最优值是:%.5f" % fitness_val_list[-1]) print("最优解是
题目来自莫烦python教学 tips: 1)当你的算法总是不收敛,诶反正就是你怎么改参数它都不收敛的时候,可能是fitness函数写错了(幽怨脸),问问自己,numpy矩阵操作对了吗? ): idx = np.random.choice(np.arange(POP_SIZE),size = POP_SIZE,replace = True,p = fitness /fitness.sum()) #print("idx : ",idx) return self.pop[idx] def mutate = self.getFitness(self.pop) + 1e-4 self.pop = self.select(fitness) #print("Gen : ",gen,"pop :",self.pop) bestRes = self.translateDNA(self.pop[np.argmax(fitness)
avg_fitness = np.mean(best_fitness_list) std_fitness = np.std(best_fitness_list) particle.fitness = fitness particle.best_fitness = fitness particle.best_position ': best_fitness, 'mean_fitness': mean_fitness, 'std_fitness': std_fitness if fitness < self.global_best_fitness: self.global_best_fitness = fitness , 'best_fitness': self.global_best_fitness, 'fitness_history': fitness_history
random.random() for i in range(self.dim)]) v.append([random.random() for m in range(self.dim)]) fitness = [self.fun(x[j]) for j in range(self.N)] p = x best = min(fitness) pg = x[fitness.index(min(fitness if min(fitness_) < best: pg = x[fitness_.index(min(fitness_))] best = min(fitness_) 4、整体代码 其中 = [self.fun(x[j]) for j in range(self.N)] p = x best = min(fitness) pg = x[fitness.index if min(fitness_) < best: pg = x[fitness_.index(min(fitness_))] best =
, population, n): total_fitness = sum(fitness) step = total_fitness / n start = random.uniform (0, step) pointers = [start + i*step for i in range(n)] selected = [] cum_fitness = 0 idx = 0 for ptr in pointers: while cum_fitness < ptr: cum_fitness += fitness ): probs = fitness / fitness.sum() return np.random.choice(len(pop), size=2, p=probs, best_idx = np.argmax(fitness) best_fitness.append(-fitness[best_idx]) # 记录实际函数值
# -*- coding: utf-8 -*- import numpy as np import matplotlib.pyplot as plt # 适应度函数 def fitness(x): return = 0 # 适应度值 def __eq__(self, other): self.x = other.x self.fitness = other.fitness # 初始化种群 def initPopulation (pop, N): for i in range(N): ind = indivdual() ind.x = np.random.uniform(-10, 10) ind.fitness = fitness = fitness(child1.x) child2.fitness = fitness(child2.x) return child1, child2 # 变异过程 def mutation(pop = fitness(ind.x) # 最终执行 def implement(): # 种群中个体数量 N = 20 # 种群 POP = [] # 迭代次数 iter_N = 500 # 初始化种群
def select_best_individuals(population, fitness, num_best): indices = np.argsort(fitness)[-num_best = np.max(fitness) print(f'Generation {generation}, Best Fitness: {best_fitness}') fitness_ga = evaluate_population(population_ga)4.3 选择父代个体根据适应度选择父代个体。 def select_parents(population, fitness, num_parents): indices = np.argsort(fitness)[-num_parents:] = np.max(fitness) print(f'Generation {generation}, Best Fitness: {best_fitness}')
maxgen= 100; % 最大迭代次数 %初始化 x =randn(popsize, birdsize); v =randn(popsize, birdsize); %初始化pid,pgd fitness =calfitness(x); pid = x; pidfit =fitness; [bfit, bfiti]= min(fitness); pgd =x(bfiti, :); pgdfit =bfit c2 .* rand .* (repmat(pgd, popsize, 1)- x); x = x + v; % 更新pid,pgd fitness = calfitness(x ); index = find(fitness < pidfit); pid(index, :) = x(index, :); pidfit(index, 1) = fitness output 适应度值 x = x .^ 2 +x - 6; fitness =sum(x, 2); end