问题
Using Microsoft Excel 2010.
Why do these two formulae produce different results?
= (0.5 - 0.4 - 0.1)
produces -2.775E-17 while
= 0.5 - 0.4 - 0.1
produces exactly 0.
The only difference is in the brackets. Does Excel try to do clever things with floating-point numbers that it thinks should be a certain value instead of another value in order to hide the usual problems of binary floating-point and make it look as though it's using decimal arithmetic? Is this documented?
来源：https://stackoverflow.com/questions/53337274/floating-point-precision-problems