Java double round 2 digit

java round double/float to 2 decimal places

You can use DecimalFormat too to round number to 2 decimal places.

Read also:

7 ways to format double to 2 decimal places in java

7 ways to format float to 2 decimal places in java

Using BigDecimal

You can convert double or float to BigDecimal and use setScale() method to round double/float to 2 decimal places.
Here is the example:

Using Math.round(double*100.0)/100.0

You must be wondering how this works.

double*100.0 – 234354.76
Math.round(double*100.0) – 234355.00 (round to nearest value)
Math.round(double*100.0)/100.0 – 2343.55

Using Apache common Math

You can also use Apache common ‘s math library to round double or float to 2 decimal places.
Add the following dependency to pom.xml .

You can find versions of commons-math over here.
Here is the example:

That’s all about rounding double/float to 2 decimal places

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Округлите число с плавающей точкой до 2 знаков после запятой в Java

В этом посте будет обсуждаться, как округлить двойное число до 2 знаков после запятой в Java.

1. Использование Math.round() метод

The Math.round() метод возвращает значение указанного двойного округления до ближайшего длинного значения. Следующее решение демонстрирует его использование для округления двойного числа до 2 знаков после запятой. Обратите внимание, что количество нулей указывает количество десятичных знаков.

Обратите внимание, что количество нулей указывает количество десятичных знаков. Поэтому, чтобы округлить до 3 знаков после запятой, выполните следующие действия:

Вот альтернативная, эквивалентная версия приведенного выше кода:

Арифметика с плавающей запятой может быть очень сложной, и этот метод также не всегда работает так, как хотелось бы. Например, значение 296.335 округляется до 296.33 вместо 296.34 .

2. Использование DecimalFormat.format() метод

Здесь идея состоит в том, чтобы создать DecimalFormat используя указанный шаблон и вызовите DecimalFormat.format() метод для получения отформатированной строки. Чтобы ограничить двойное значение двумя десятичными точками, вы можете использовать шаблон #.## . Вы также можете установить RoundingMode с использованием setRoundingMode() метод. Этот подход страдает той же проблемой, что и первый подход. т. е. значение 296.335 округляется до 296.33 вместо 296.34 .

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Round a Double to Two Decimal Places in Java

1. Round of a double to Two Decimal Places Using Math.round(double*100.0)/100.0
2. Round of a double to Two Decimal Places Using BigDecimal
3. Round of a double to Two Decimal Places Using DecimalFormat
4. Round of a double to Two Decimal Places Using Apache Common Math

In the previous tutorial article, we have understood how to convert an Array to ArrayList in Java using various methods with detailed examples. We will look at more types of Java usage through different forms of scenario analysis.

In this tutorial article, we will discuss on rounding of a double to two decimal places using Java. There are four ways to round up a double value to two decimal places such as Math.round() , BigDecimal using the setScale() method, DecimalFormat and Apache Common library.

Let us discuss each way through examples.

Round of a double to Two Decimal Places Using Math.round(double*100.0)/100.0

The Math.round() method is used in Java to round a given number to its nearest integer. Since in this article, we will learn rounding of a double to 2 decimal places, the application of Math.round() will include (double*100.0)/100.0 .

Let us follow the below example.

import java.util.*; import java.lang.*; import java.io.*;  public class Main   public static void main(String[] args)    double d = 7435.9876;  double roundDbl = Math.round(d*100.0)/100.0;  System.out.println("Rounded Double value: "+roundDbl);  > > 

Rounded Double value: 7435.99 

Round of a double to Two Decimal Places Using BigDecimal

In this way, we can first convert double to BigDecimal and then use the setScale() method to round the converted BigDecimal to two decimal places. Let us understand the below example.

import java.util.*; import java.lang.*; import java.io.*; import java.math.BigDecimal; import java.math.RoundingMode;  public class Main   public static void main(String[] args)    double val1 = 4312.186462;  System.out.println("Double value: "+val1);   BigDecimal bd = new BigDecimal(val1).setScale(2, RoundingMode.HALF_UP);  double val2 = bd.doubleValue();  System.out.println("Rounded Double value: "+val2);  > > 

Double value: 4312.186462 Rounded Double value: 4312.19 

Round of a double to Two Decimal Places Using DecimalFormat

We can also round a double value to two decimal places using DecimalFormat . Let us discuss in the following example.

import java.util.*; import java.lang.*; import java.io.*; import java.text.DecimalFormat;  public class Main   public static void main(String[] args)    double val1 = 6482.236789;  System.out.println("Double value: "+val1);   DecimalFormat df = new DecimalFormat("###.##");  System.out.println("Rounded Double value (DecimalFormat): "+df.format(val1));  > > 

Double value: 6482.236789 Rounded Double value: 6482.24 

Round of a double to Two Decimal Places Using Apache Common Math

A special kind of math library in Java is used to round a double to two decimal places, which is Apache Common . Let us discuss its utilization in the following example.

We need to add this library dependency in an xml file within the Java project.

   org.apache.commons   commons-math3   3.6.1  

Now let’s check the apache library implementation for rounding a double to two decimal places.

import java.util.*; import java.lang.*; import java.io.*; import org.apache.commons.math3.util.Precision;  public class Main   public static void main(String[] args)    double input = 9476.2351;  double roundedDbl = Precision.round(input,2);  System.out.println("Rounded Double value: "+roundedDbl);  > > 

Rounded Double value: 9476.24 

It is recommended to follow the first three ways for simple Java applications.

Related Article — Java Double

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How to Round Float or Double in Java

In this tutorial, you will learn how to round a Float or a Double value to 2 decimal places in Java.

1. Using BigDecimal

One of the ways to round a float or a double value is to use BigDecimal class.

BigDecimal bigDecimalDouble = new BigDecimal(doubleValue);

BigDecimal class allows us to set a scale and a rounding mode.

bigDecimalDouble.setScale(2, RoundingMode.HALF_UP);

• scale – is a number of decimal points,
• RoundingMode.HALF_UP – is a rounding mode used. Other rounding modes are:
  • ROUND_UP,
  • ROUND_DOWN,
  • ROUND_CEILING,
  • ROUND_FLOOR,
  • ROUND_HALF_DOWN,
  • ROUND_HALF_EVEN,
  • ROUND_UNNECESSARY

  BigDecimal – Round double to 2 decimal points example

  import java.math.BigDecimal; import java.math.RoundingMode; public class RoundDouble < public static void main(String args[]) < double doubleValue = 11.8989; BigDecimal bigDecimalDouble = new BigDecimal(doubleValue); System.out.println(bigDecimalDouble); // Prints 11.8988999999999993661958797019906342029571533203125 BigDecimal bigDecimalWithScale = bigDecimalDouble.setScale(2, RoundingMode.HALF_UP); System.out.println(bigDecimalWithScale); // Prints 11.90 >>

  Similarly, you can use BigDecimal to round a float value to 2 decimal points.

  BigDecimal – Round float to 2 decimal points example

  import java.math.BigDecimal; import java.math.RoundingMode; public class RoundDouble < public static void main(String args[]) < float floatValue = 11.8989f; BigDecimal bigDecimalFloat = new BigDecimal(floatValue); System.out.println(bigDecimalFloat); // Prints 11.89890003204345703125 BigDecimal bigDecimalFloatWithScale = bigDecimalFloat.setScale(2, RoundingMode.HALF_UP); System.out.println(bigDecimalFloatWithScale); // Prints 11.90 >>

  2. Using DecimalFormat

  Another way to round a float or a double value to 2 decimal points is to use the DecimalFormat class. DecimalFormat class allows us to create an output pattern and then set a rounding mode that we want to apply to a value.

  Round to 2 decimal points

  DecimalFormat decimalFormat = new DecimalFormat("0.00"); decimalFormat.setRoundingMode(RoundingMode.HALF_UP);

  Round to 1 decimal point

  DecimalFormat decimalFormat = new DecimalFormat("0.0"); decimalFormat.setRoundingMode(RoundingMode.HALF_UP);

  Format Pattern “0.00” vs “#.##”

  Both of these formatting patterns work similarly, except that “#.##” will not display a digit if the last decimal point is zero. For example,

  if doubleValue = 11.90 then BigDecimal("#.##") will print 11.9

  On the other hand, the formatting pattern “0.00” will always display a digit even if it is zero. For example,

  if doubleValue = 11.90 then BigDecimal("0.00") will print 11.90

  Rounding Modes:

  • ROUND_UP,
  • ROUND_DOWN,
  • ROUND_CEILING,
  • ROUND_FLOOR,
  • ROUND_HALF_DOWN,
  • ROUND_HALF_EVEN,
  • ROUND_UNNECESSARY

  Let’s have a look at the complete example.

  Decimal Format – Round double to 2 decimal points example

  import java.math.BigDecimal; import java.math.RoundingMode; import java.text.DecimalFormat; public class RoundDouble < public static void main(String args[]) < double doubleValue = 11.8989; DecimalFormat decimalFormat = new DecimalFormat("0.00"); decimalFormat.setRoundingMode(RoundingMode.HALF_UP); System.out.println(decimalFormat.format(doubleValue)); //11.90 >>

  Decimal Format – Round float to 2 decimal points example

  import java.math.RoundingMode; import java.text.DecimalFormat; public class RoundFloat < public static void main(String args[]) < float floatValue = 11.8989f; DecimalFormat decimalFormat = new DecimalFormat("0.00"); decimalFormat.setRoundingMode(RoundingMode.HALF_UP); System.out.println(decimalFormat.format(floatValue)); //11.90 >>

  3. Using String.format(“%.2f”, floatValue)

  Alternatively, you can use String.format() function to format the input value to 2 decimal points. Although, String.format() does not allow to change the rounding mode. The only rounding mode applicable is half-up.

  I hope this tutorial was helpful for you.

  There are many other useful tutorials you can find on this site. To find Java-related tutorials, check out the Java tutorials page.

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