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PHP 概率计算显示问题

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Jun 23, 2016 pm 02:03 PM

我现在有2个数组：
$arr_str=array(1,3,2,3,5,2); //需要显示键值的数组
$chance_str=array(0.25,0.27,0.98,0.58,0.33,0.25); //显示数值的概率数组

现在每次访问页面的时候，值显示$arr_str中的一个键值，
每次显示这个键值的概率是$chance_str来控制，肯定会有总和大于100%的时候
这$chance_str的键值是会实时修改的，这个我该咋弄呢，各位大侠帮帮忙！

回复讨论(解决方案)

$chance_str
将这个数组每一个都 X100，确定每一个都是整数

然后把每个元素相加得总和 $count

再生成一个随机数，0 - $count

看随机数在哪个区间

0-25则在第一区间
26 - (25+27) 第二区间
(25+27)+1 - (25+27+98) 第三区间，如此累推。。。。

echo array_sum($chance_str); //2.66
无论怎么做都不可能完成这样的概率分布

问题是你的概率是怎么定的？定义的方法不同自然就不同

如果每次只显示一个数，全部完成为1.00，则属于不可能的任务，而且有个0.98简直就是离谱

但如果每次显示多个数，还是有可能做到的
就是“概率”的概念转为“权重”的概念，权重总和可以>1，也可以有权重叠加的情况

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