Java Double Multiplication explanation? [duplicate

问题:

This question already has an answer here:

• Moving decimal places over in a double 9 answers

I recently tested something out that I heard using the following code

public static void main(String[] args) { double x = 4.35 * 100; System.out.println(x); }.

I am interested as to why this produces 434.99999999999994 rather than 435.0 . Thanks

回答1:

when you type

double x = 4.35;

x is not stored as-is. It is stored in a approaching form (probably 4.349999999 in this case).

If you want exact result, please use BigDecimal.