Java Essay: float, double precision

Typically, a float or double is used to calculate the currency.

What does the following calculation output?

System.out.println (2.00-1.10);

Started thinking it would be 0.90, the actual result is: 0.8999999999999999

The reason is that not all decimals can be accurately represented by binary floating point.

How to transform it?

• Use int, long to calculate, and then convert to floating point number.
• Use BigDecimal to calculate.

System.out.println (New BigDecimal ("2.00"). Subtract (New BigDecimal ("1.10"));

This will get the result we want: 0.90

Note: When using BigDecimal, if this is initialized, you will get the result of failure.

System.out.println (New BigDecimal (2.00) Subtract (new BigDecimal (1.10)));

In this case, the result is: 0.899999999999999911182158029987476766109466552734375

Java Essay: float, double precision