java - Java中具有 double 的奇数结果

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我只是试图计算percent_imp，但不是0.22（精确为0.22，没有舍入错误），而是得到0.22000000000000003！
我曾经得到类似的奇数结果，并且被告知要从float变为double，但是这个仍然很奇怪！
以下所有变量都是双精度！

double percentage_imp= budget -  (sum_minlessi)/ (sum_i + sum_lessi);

最佳答案

那是因为浮点精度值。

您必须阅读：-What Every Computer Scientist Should Know About Floating-Point Arithmetic

您还必须阅读how floating point arithmetic and its internal representation works。