Set precision in java

4 Methods to Set Precision for Decimal Numbers in Java

Learn how to set precision for decimal numbers in Java using DecimalFormat, Math.round(), BigDecimal class, and NumberFormat class. Get examples and choose the appropriate method for your use case.

• Using DecimalFormat to Format Decimal Numbers
• Using Math.round() Method to Round Numbers to Specific Decimal Places
• Formatting Decimals in Java
• Using BigDecimal Class to Round Numbers to Specific Decimal Places
• Formatting Decimal Numbers as Currency Using NumberFormat Class
• Other simple code examples for rounding decimal numbers in Java
• Conclusion
• How to set decimal places in Java?
• How do I restrict to 2 decimal places in Java?
• How to format to 3 decimal places in Java?
• What is .2f in Java?

Java is a popular programming language widely used in software development and information technology. It provides multiple ways to set precision for double values and round numbers to specific decimal places. This is essential for applications that require accurate financial calculations or the display of numerical data. In this blog post, we will explore different methods to set precision for double values in java and round numbers to specific decimal places to meet the user’s intent.

Using DecimalFormat to Format Decimal Numbers

DecimalFormat is a child class of NumberFormat and can be used to format decimal numbers and specify rounding behavior. The format specifier %.2f can be used with the printf function to format a double to two decimal places. RoundingMode can be used with DecimalFormat to specify rounding behavior. Examples of using DecimalFormat to format decimal numbers with specific decimal places and rounding behavior are as follows:

import java.text.DecimalFormat; import java.math.RoundingMode;public class DecimalFormatExample < public static void main(String args[]) < double num = 123.456789; DecimalFormat df = new DecimalFormat("#.##"); df.setRoundingMode(RoundingMode.CEILING); System.out.println("Formatted number with two decimal places: " + df.format(num)); >> 

The output of the above code will be:

Formatted number with two decimal places: 123.46 

In the code example above, we have used DecimalFormat to format the double value to two decimal places with the CEILING rounding mode. We can change the rounding mode according to our requirements.

Using Math.round() Method to Round Numbers to Specific Decimal Places

The Math.round() method can also be used to control the number of decimal places. The default rounding mode for Math.round() is to round to the nearest integer. Examples of using Math.round() method to round numbers to specific decimal places and control rounding mode are as follows:

public class MathRoundExample < public static void main(String args[]) < double num = 123.456789; double roundedNum = Math.round(num * 100.0) / 100.0; System.out.println("Rounded number with two decimal places: " + roundedNum); >> 

The output of the above code will be:

Rounded number with two decimal places: 123.46 

In the code example above, we have used Math.round() method to round the double value to two decimal places by multiplying the number by 100, rounding it to the nearest integer, and then dividing it by 100.

Formatting Decimals in Java

Java: Rounding Numbers (Math.round(), DecimalFormat & printf) · Java — Long, Float and Duration: 5:03

Using BigDecimal Class to Round Numbers to Specific Decimal Places

BigDecimal class can also be used to round numbers to specific decimal places. BigDecimal.setScale() method can be used to set scale and rounding mode. Examples of using BigDecimal class to round numbers to specific decimal places with different rounding modes are as follows:

import java.math.BigDecimal; import java.math.RoundingMode;public class BigDecimalExample < public static void main(String args[]) < double num = 123.456789; BigDecimal bd = new BigDecimal(num); bd = bd.setScale(2, RoundingMode.CEILING); System.out.println("Rounded number with two decimal places: " + bd); >> 

The output of the above code will be:

Rounded number with two decimal places: 123.46 

In the code example above, we have used BigDecimal class to round the double value to two decimal places with CEILING rounding mode.

Formatting Decimal Numbers as Currency Using NumberFormat Class

The NumberFormat.getCurrencyInstance() method can be used to format decimal numbers as currency. Examples of using NumberFormat class to format decimal numbers as currency with specific decimal places and rounding behavior are as follows:

import java.text.NumberFormat; import java.util.Locale;public class CurrencyFormatExample < public static void main(String args[]) < double num = 123.456789; NumberFormat currencyFormatter = NumberFormat.getCurrencyInstance(Locale.US); currencyFormatter.setMaximumFractionDigits(2); currencyFormatter.setMinimumFractionDigits(2); System.out.println("Formatted currency: " + currencyFormatter.format(num)); >> 

The output of the above code will be:

In the code example above, we have used NumberFormat class to format the double value as currency with two decimal places and the US locale.

Other simple code examples for rounding decimal numbers in Java

In Java , how to set 2 decimal places in java code example

DecimalFormat df = new DecimalFormat(); df.setMaximumFractionDigits(2); System.out.println(df.format(decimalNumber));

In Java as proof, decimals java

// Java Program to Round a Number to n Decimal Places // using format() Method // Importing required classes import java.io.*; // Main class class GFG < // Main driver method public static void main(String[] args) < // Declaring and initializing a double number double number = 3.141341435; // Rounding number to 2 decimal places // using format method System.out.format("%.2f", number); >>

In Java case in point, specify decimal places java code sample

double test = 12.15; DecimalFormat df = new DecimalFormat("#.0"); System.out.println(df.format(test)); // Console: 12.2 // # - prints a digit if provided, nothing otherwise // . - indicates where to put the decimal seperator // 0 - prints a digit if provided, 0 otherwise

In Java as proof, how to get 2 decimal places in java code sample

total = (double) 100 / listMember.size(); DecimalFormat df = new DecimalFormat("#.##"); String dx = df.format(total); total = Double.valueOf(dx);

In Java case in point, java 2 decimals code example

double res = Math.round(a * 100) / 100;

Conclusion

Java provides multiple ways to set precision for double values and round numbers to specific decimal places. Using DecimalFormat, Math.round() method, and BigDecimal class are some of the ways to achieve this. It is important to choose the appropriate method based on the specific use case and requirements. By understanding these methods, Java developers can ensure accurate financial calculations and display of numerical data in their applications.

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4 Methods to Set Precision for Decimal Numbers in Java

Learn how to set precision for decimal numbers in Java using DecimalFormat, Math.round(), BigDecimal class, and NumberFormat class. Get examples and choose the appropriate method for your use case.

• Using DecimalFormat to Format Decimal Numbers
• Using Math.round() Method to Round Numbers to Specific Decimal Places
• Formatting Decimals in Java
• Using BigDecimal Class to Round Numbers to Specific Decimal Places
• Formatting Decimal Numbers as Currency Using NumberFormat Class
• Other simple code examples for rounding decimal numbers in Java
• Conclusion
• How to set decimal places in Java?
• How do I restrict to 2 decimal places in Java?
• How to format to 3 decimal places in Java?
• What is .2f in Java?

Java is a popular programming language widely used in software development and information technology. It provides multiple ways to set precision for double values and round numbers to specific decimal places. This is essential for applications that require accurate financial calculations or the display of numerical data. In this blog post, we will explore different methods to set precision for double values in java and round numbers to specific decimal places to meet the user’s intent.

Using DecimalFormat to Format Decimal Numbers

DecimalFormat is a child class of NumberFormat and can be used to format decimal numbers and specify rounding behavior. The format specifier %.2f can be used with the printf function to format a double to two decimal places. RoundingMode can be used with DecimalFormat to specify rounding behavior. Examples of using DecimalFormat to format decimal numbers with specific decimal places and rounding behavior are as follows:

import java.text.DecimalFormat; import java.math.RoundingMode;public class DecimalFormatExample < public static void main(String args[]) < double num = 123.456789; DecimalFormat df = new DecimalFormat("#.##"); df.setRoundingMode(RoundingMode.CEILING); System.out.println("Formatted number with two decimal places: " + df.format(num)); >> 

The output of the above code will be:

Formatted number with two decimal places: 123.46 

In the code example above, we have used DecimalFormat to format the double value to two decimal places with the CEILING rounding mode. We can change the rounding mode according to our requirements.

Using Math.round() Method to Round Numbers to Specific Decimal Places

The Math.round() method can also be used to control the number of decimal places. The default rounding mode for Math.round() is to round to the nearest integer. Examples of using Math.round() method to round numbers to specific decimal places and control rounding mode are as follows:

public class MathRoundExample < public static void main(String args[]) < double num = 123.456789; double roundedNum = Math.round(num * 100.0) / 100.0; System.out.println("Rounded number with two decimal places: " + roundedNum); >> 

The output of the above code will be:

Rounded number with two decimal places: 123.46 

In the code example above, we have used Math.round() method to round the double value to two decimal places by multiplying the number by 100, rounding it to the nearest integer, and then dividing it by 100.

Formatting Decimals in Java

Java: Rounding Numbers (Math.round(), DecimalFormat & printf) · Java — Long, Float and Duration: 5:03

Using BigDecimal Class to Round Numbers to Specific Decimal Places

BigDecimal class can also be used to round numbers to specific decimal places. BigDecimal.setScale() method can be used to set scale and rounding mode. Examples of using BigDecimal class to round numbers to specific decimal places with different rounding modes are as follows:

import java.math.BigDecimal; import java.math.RoundingMode;public class BigDecimalExample < public static void main(String args[]) < double num = 123.456789; BigDecimal bd = new BigDecimal(num); bd = bd.setScale(2, RoundingMode.CEILING); System.out.println("Rounded number with two decimal places: " + bd); >> 

The output of the above code will be:

Rounded number with two decimal places: 123.46 

In the code example above, we have used BigDecimal class to round the double value to two decimal places with CEILING rounding mode.

Formatting Decimal Numbers as Currency Using NumberFormat Class

The NumberFormat.getCurrencyInstance() method can be used to format decimal numbers as currency. Examples of using NumberFormat class to format decimal numbers as currency with specific decimal places and rounding behavior are as follows:

import java.text.NumberFormat; import java.util.Locale;public class CurrencyFormatExample < public static void main(String args[]) < double num = 123.456789; NumberFormat currencyFormatter = NumberFormat.getCurrencyInstance(Locale.US); currencyFormatter.setMaximumFractionDigits(2); currencyFormatter.setMinimumFractionDigits(2); System.out.println("Formatted currency: " + currencyFormatter.format(num)); >> 

The output of the above code will be:

In the code example above, we have used NumberFormat class to format the double value as currency with two decimal places and the US locale.

Other simple code examples for rounding decimal numbers in Java

In Java , how to set 2 decimal places in java code example

DecimalFormat df = new DecimalFormat(); df.setMaximumFractionDigits(2); System.out.println(df.format(decimalNumber));

In Java as proof, decimals java

// Java Program to Round a Number to n Decimal Places // using format() Method // Importing required classes import java.io.*; // Main class class GFG < // Main driver method public static void main(String[] args) < // Declaring and initializing a double number double number = 3.141341435; // Rounding number to 2 decimal places // using format method System.out.format("%.2f", number); >>

In Java case in point, specify decimal places java code sample

double test = 12.15; DecimalFormat df = new DecimalFormat("#.0"); System.out.println(df.format(test)); // Console: 12.2 // # - prints a digit if provided, nothing otherwise // . - indicates where to put the decimal seperator // 0 - prints a digit if provided, 0 otherwise

In Java as proof, how to get 2 decimal places in java code sample

total = (double) 100 / listMember.size(); DecimalFormat df = new DecimalFormat("#.##"); String dx = df.format(total); total = Double.valueOf(dx);

In Java case in point, java 2 decimals code example

double res = Math.round(a * 100) / 100;

Conclusion

Java provides multiple ways to set precision for double values and round numbers to specific decimal places. Using DecimalFormat, Math.round() method, and BigDecimal class are some of the ways to achieve this. It is important to choose the appropriate method based on the specific use case and requirements. By understanding these methods, Java developers can ensure accurate financial calculations and display of numerical data in their applications.

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Precision on a number format in Java

On floating point, the number of decimal places is known.

Let’s say we declared a Formatter object −

Formatter f1 = new Formatter();

Now, we want 3 decimal places. For that, use 1.3f −

f1.format("%1.3f", 29292929.98765432);

The above will return the number with 3 decimal places −

The following is the final example −

Example

import java.util.Formatter; public class Demo   public static void main(String args[])   Formatter f1, f2, f3; f1 = new Formatter(); f1.format("%1.3f", 29292929.98765432); System.out.println(f1); f2 = new Formatter(); f2.format("%1.7f", 29292929.98765432); System.out.println(f2); f3 = new Formatter(); f3.format("%1.9f", 29292929.98765432); System.out.println(f3); > >

Output

29292929.988 29292929.9876543 292929.987654320

I love programming (: That’s all I know

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