Note: Just like String, BigDecimal objects are immutable. It is used to represent double as a string with a specified number of digits after the. Output: Converted BigDecimal to Double: 3456.78912 Converting BigDecimal to Double with 2 Decimal places After converting BigDecimal to Double, you can easily restrict the Double to 2 decimal places by using BigDecimal class setScale () method as shown below in the example. To restrict the double to 2-decimal points, you can use the pattern. On the other hand, if it's only the display value you care about, you can control that using output formatting options. Double value can be converted to string using the String.format() method. format() method to get the formatted string. So you get terms like "accurate to 14-1/2 digits".Īs others have already said, if you want EXACTLY 2 decimal places, you need a non-floating number type such as BigNumber. They can be equated to an approximate number of decimal places, but the actual decimal precision varies depending on the numerical value, even if one disregards decimal/binary precision issues. What you'd get back would be inaccurate.Īctually, the number of binary places for float and double values are fixed by their respective format definitions, not definable by the application programmer. The IEEE floating-point format that Java uses has binary fractions, not decimal ones, so it would be impossible to return a "double with 2 decimal places" for the same reason that you can't return 1/3 to 2 decimal places. Of course, there's a fundamental problem with that. The correct question would have been "how to return double with 2 decimal places. C C++ C D Dart Elixir Erlang Fortran Go Haskell JS Java Lua PHP Pascal Perl Python Python Ruby Rust. That's the delineation (point) between the integral part of the number and the fractional part. You can use s format() method to format double to 2 decimal places. However, it is just possible that you need an exact value to 2 decimal places - for example, to hold an amount of money in dollars - and if that's the case then you have no alternative but to use BigDecimal (as you already did) and forget about doubles altogether.īut whatever you do, don't, don't, DON'T change the return type to a String just because it doesn't look right.įloating point numbers have only ONE decimal point. To get the formatted String, and then just print that. If you want to display a double rounded to two decimal points, then use: You seem to be hung up on this notion of 2 decimal places, when in fact it's just a formatting issue. I had to redesign the function to return string instead of double. So there is no such thing as a "double with two decimal points". Ramy Nady wrote:I have tried BigDecimal with setScale, the BigDecimal itself has the two digits but whenever I convert it to double still keeping one digitĪ double (or Double) has no notion of how many "decimal points" it holds it's simply a value - and often an inexact one at that (read this). I hope I haven't muddled things I am saying that if the input was already limited to two digits of precision, and is less than roughly 10^14, your original solution is already working and you just may be misled by what () displays. How to convert a double value to String in Java - The double data type in Java stores double-precision 64-bit IEEE 754 floating point number. You may think you're incorrectly returning "10.0" because that's what you see when you convert it to a String and display it on the console. You can return that, and you will have met the requirements of the problem as described. Second, if the string cannot be parsed as a Double, an exception will be thrown. Let us see each method in detail with an example below. There may be situations, where we want to limit the number of digits after the decimal. For this, the input string is generally a float or a double value, which consists of several digits after the decimal point. First, if the string has more than two decimal places, the extra decimal places will be truncated. There are different methods to round a number to n decimal places in Java. When you need to convert a string to a double, there are a few things you need to keep in mind. "10.00" (String) successfully parses to a double representing 1 x 10^1. Java Convert String to Double With 2 Decimal Places. However, if your function needs to return a double, as you have shown in your follow-up posting, then maybe I need to better understand the problem. If your function needs to have a fixed precision (2 digits in this case) BigDecimal is the way to go for parsing the String. I agree with Jeanne and just want to expand on her advice. Jeanne Boyarsky wrote:The problem is that double doesn't support a fixed number of decimal points.
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