Precision loss in float and double subtraction operations

Precision loss occurs when the float and double types perform subtraction. This problem is mainly caused by the widespread use of binary in computers. This is a record to prevent future forgetting.

Public static void main (string [] ARGs) {float a = 2.1f; float B = 2.0f; float c = A-B; system. out. println ("a-B =" + C);} // output: A-B = 0.099999905

In this case, you need to use the bigdecimal class

Bigdecimal add (bigdecimalaugend) addition operation

Bigdecimal subtract (bigdecimal subtrahend) subtraction operation

Bigdecimal multiply (bigdecimal multiplicand) Multiplication

Bigdecimal divide (bigdecimal divisor) division operation

Public static void main (string [] ARGs) {float a = 2.1f; float B = 2.0f; bigdecimal a1 = new bigdecimal (float. tostring (a); bigdecimal b1 = new bigdecimal (float. tostring (B); float C1 = a1.subtract (B1 ). floatvalue (); system. out. println ("a1-b1 =" + C1);} // output: a1-b1 = 0.1

Detailed principle reference http://www.blogjava.net/jelver/articles/340038.html

This article is from the blog "plug on the name of pigs", please be sure to keep this source http://zuohao1990.blog.51cto.com/6057850/1560642

Precision loss in float and double subtraction operations