# double « decimal « Java Data Type Q&A

### 1. Sum of decimal number in java    stackoverflow.com

I have a problem for the managemente of decimal number in java (JDK 1.4). I have two double numbers first and second (as output of formatted String). I do a sum between ...

### 6. how to read the decimal portion of a double number? (using scanner method)    forums.oracle.com

hello Java pros.... I need to read the integer and decimal part of a double number, one independently of the other. I must be able to assign the integer part to a variable, and the decimal part to a different variable. Is there a method that does what I need directly after reading the initial value (double) ? or, should I ...

### 7. Doubles and decimals - fatal calculation mistakes    forums.oracle.com

Floating point numbers build their fractions out of unique negative powers of two, i.e. 1/2, 1/4, 1/8 ... 1/2^n. You can't construct 1/10 (decimal) out of those fractions so you have to work with approximations; just like we do with decimal expansions of, say, 1/3; we can't exactly represent that number using decimal fractions 1/10, 1/100 ... 1/10^n either kind regards, ...

### 10. Limiting double's decimals    forums.oracle.com

This is probably a simple one, but here goes. Normally java will display an irrational number in the following form "37.666666666666664" How do I edit this so that it is "37.66" or "37.67"? Since I am writing my output to a text file, this is quite bothersome that there are so many decimals since it looks rather ugly