小编use*_*367的帖子

java中两个双数的总和是无穷大

即使这些数字不是无穷大,两个double的总和也是无穷大.代码如下.

entropy += (probs.get(key)* (Math.log(probs.get(key)) / Math.log(2.0)));
    if(entropy == Double.POSITIVE_INFINITY || entropy == Double.NEGATIVE_INFINITY){
        System.out.println("Prob:"+probs.get(key));
        System.out.println("base 10: "+Math.log(probs.get(key)));
        System.out.println("base 2: "+Math.log(2.0));
        System.out.println("result: "+(probs.get(key)*(Math.log(probs.get(key))) / Math.log(2.0)));
        System.out.println("entropy before sum "+temp);
        break;
    }`
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结果是:

Prob:1.0476603084695572E305
base 10: 702.3350127634005
base 2: 0.6931471805599453
result: 1.0615472972511642E308
entropy before sum: 1.246498306457423E308
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那怎么可能总和

result + entropy = 1.0615472972511642E308 + 1.246498306457423E308 = INFINITY

java double sum infinity

5
推荐指数
1
解决办法
1571
查看次数

在python中创建一个包含\ x的字符串

我想创建一个包含"\ x"的字符串,但我得到了

invalid \x escape
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错误.

a = '\x'+''.join(lstDES[100][:2])+'\x'+''.join(lstDES[100][2:])
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我该如何纠正?

python string special-characters

1
推荐指数
1
解决办法
3038
查看次数

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