import numpy as np def roulette(probability): probabilityTotal = np.zeros(len(probability)) probabilityTmp = 0 for i in range(len(probability)): probabilityTmp += probability[i] probabilityTotal[i] = probabilityTmp randomNumber=np.random.rand() result=0 for i in range(1, len(probabilityTotal)): if randomNumber<probabilityTotal[0]: result=0 print("random number:",randomNumber,"<index 0:",probabilityTotal[0]) break elif probabilityTotal[i - 1] < randomNumber <= probabilityTotal[i]: result=i print("index ",i-1,":",probabilityTotal[i-1],"<random number:",randomNumber,"<index ",i,":",probabilityTotal[i]) return result probability=[0.39897898,0.05301439,0.03615747,0.02251049,0.02993633,0.02285509,0.01361222,0.03879427,0.01937278,0.0274668,0.02173864,0.03050861,0.01137698,0.00821177,0.01364433,0.01546327,0.05063628,0.03238738,0.03441008,0.01896785,0.01343442,0.01250853,0.00500341,0.01080083,0.01227628,0.00865885,0.01000899,0.01326119,0.0140035] result=np.zeros(100).astype(int) count=np.zeros(100).astype(int) for i in range(100): print("loop",i) result[i]=roulette(probability) count[result[i]]+=1 print("result:",result) print("count:",count)
时间: 2023-06-14 16:03:56 浏览: 105
这段代码实现了一个轮盘赌算法,用于从一组概率值中随机选择一个值。具体而言,该函数接受一个概率值列表作为输入,返回一个在0到len(probability)-1之间的整数,表示随机选择的概率值的索引。
在上面的代码中,我们定义了一个名为roulette的函数,其中包含了轮盘赌算法的实现。该函数首先将输入的概率值列表中的每个概率值累加起来,得到一个新的列表probabilityTotal,其中每个元素表示前n个概率值的累加和。接着,该函数生成一个0到1之间的随机数randomNumber,然后利用这个随机数来选择一个概率值。具体而言,该函数从probabilityTotal列表中找到第一个比随机数randomNumber大的元素的索引,然后返回该索引值减去1。
为了测试该函数的效果,我们在代码中定义了一个概率值列表probability,其中包含了30个概率值。然后,我们利用一个循环,调用该函数100次,得到100个随机选择的概率值的索引。最后,我们统计每个索引值出现的次数,以此来验证随机选择的概率是否符合输入的概率分布。
需要注意的是,在该代码中,我们使用了numpy库来处理数组和随机数的生成。因此,在运行代码之前,需要确保已经安装了numpy库。
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