How to get the value without round up/down in Java?

Question

double d0 = Double.parseDouble("53.82233040000000557");
double d1 = Double.valueOf("53.82233040000000557");

output

d0 = 53.822330400000006
d1 = 53.822330400000006

Answer 1

Precision Numbers in Java

Class java.math.BigDecimal is better for handling numbers where precision matters (like monetary amounts), see BigDecimal VS double.

It could be used for geo-coordinates (latitude/longitude). Although practitionars argue that double is precise enough for lat./long. - since you don't want to locate something at nano-meter scale.

Example Code

If you need high precision and scale for your number, use BigDecimal like this:

BigDecimal decimalValue = new BigDecimal("53.82233040000000557");
System.out.println("as BigDecimal: " + decimalValue.toPlainString());
// prints exactly: 53.82233040000000557

Run this code online (IDE one): Double VS BigDecimal for high precision

Read more

Read more in a tutorial on Java: BigDecimal and BigInteger

Answer 2

If you need precision, you have to use a BigDecimal.

Answer 3

The answer is that you cannot. The values you are getting are the most accurate approximation to your values that can possibly be stored in a double. There is no possible way to get a more accurate, less rounded value stored in a double.

If you require that the answers are not rounded at all, therefore, you should not be using double. The data type you should be using instead is BigDecimal.