How to REDUCE decimal values from a value of type 'double' in Java

Question

This is probably a really simple question but, is there a simple way to go from

Double myLongNumber = 50.12345678998658576546

to

Double myLongNumber = 50.1234

?

I just want to reduce the number of decimal digits, not remove them all.

Answer 1

If you really want to change that number, you can do something like

Double myNotSoLongNumber = Math.round(myLongNumber * 1E4) / 1E4;

If you want to display a Double with less fraction digits, use

String myLongNumberAsString = String.format("%.4f", myLongNumber);