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How to print a float with 2 decimal places in Java?

Can I do i开发者_运维技巧t with System.out.print?


You can use the printf method, like so:

System.out.printf("%.2f", val);

In short, the %.2f syntax tells Java to return your variable (val) with 2 decimal places (.2) in decimal representation of a floating-point number (f) from the start of the format specifier (%).

There are other conversion characters you can use besides f:

  • d: decimal integer
  • o: octal integer
  • e: floating-point in scientific notation


You can use DecimalFormat. One way to use it:

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

Another one is to construct it using the #.## format.

I find all formatting options less readable than calling the formatting methods, but that's a matter of preference.


I would suggest using String.format() if you need the value as a String in your code.

For example, you can use String.format() in the following way:

float myFloat = 2.001f;

String formattedString = String.format("%.02f", myFloat);


double d = 1.234567;
DecimalFormat df = new DecimalFormat("#.##");
System.out.print(df.format(d));


float f = 102.236569f; 
DecimalFormat decimalFormat = new DecimalFormat("#.##");
float twoDigitsF = Float.valueOf(decimalFormat.format(f)); // output is 102.24


You may use this quick codes below that changed itself at the end. Add how many zeros as refers to after the point

float y1 = 0.123456789;
DecimalFormat df = new DecimalFormat("#.00");  
y1 = Float.valueOf(df.format(y1));

The variable y1 was equals to 0.123456789 before. After the code it turns into 0.12 only.


float floatValue=22.34555f;
System.out.print(String.format("%.2f", floatValue));

Output is 22.35. If you need 3 decimal points change it to "%.3f".


Many people have mentioned DecimalFormat. But you can also use printf if you have a recent version of Java:

System.out.printf("%1.2f", 3.14159D);

See the docs on the Formatter for more information about the printf format string.


A simple trick is to generate a shorter version of your variable by multiplying it with e.g. 100, rounding it and dividing it by 100.0 again. This way you generate a variable, with 2 decimal places:

double new_variable = Math.round(old_variable*100) / 100.0;

This "cheap trick" was always good enough for me, and works in any language (I am not a Java person, just learning it).


Look at DecimalFormat

Here is an example from the tutorial:

  DecimalFormat myFormatter = new DecimalFormat(pattern);
  String output = myFormatter.format(value);
  System.out.println(value + "  " + pattern + "  " + output);

If you choose a pattern like "###.##", you will get two decimal places, and I think that the values are rounded up. You will want to look at the link to get the exact format you want (e.g., whether you want trailing zeros)


To print a float up to 2 decimal places in Java:

    float f = (float)11/3;
    System.out.print(String.format("%.2f",f));

OUTPUT: 3.67

> use %.3f for up to three decimal places.


Below is code how you can display an output of float data with 2 decimal places in Java:

float ratingValue = 52.98929821f; 
DecimalFormat decimalFormat = new DecimalFormat("#.##");
float twoDigitsFR = Float.valueOf(decimalFormat.format(ratingValue)); // output is 52.98


OK - str to float.

package test;

import java.text.DecimalFormat;

public class TestPtz {
  public static void main(String[] args) {
    String preset0 = "0.09,0.20,0.09,0.07";
    String[] thisto = preset0.split(",");    
    float a = (Float.valueOf(thisto[0])).floatValue();
    System.out.println("[Original]: " + a);   
    a = (float) (a + 0.01);

    // Part 1 - for display / debug
    System.out.printf("[Local]: %.2f \n", a);
    // Part 2 - when value requires to be send as it is
    DecimalFormat df = new DecimalFormat();
    df.setMinimumFractionDigits(2);
    df.setMaximumFractionDigits(2);
    System.out.println("[Remote]: " + df.format(a));

  }
}

Output:

run:
[Original]: 0.09
[Local]: 0.10 
[Remote]: 0.10
BUILD SUCCESSFUL (total time: 0 seconds)


One issue that had me for an hour or more, on DecimalFormat- It handles double and float inputs differently. Even change of RoundingMode did not help. I am no expert but thought it may help someone like me. Ended up using Math.round instead. See below:

    DecimalFormat df = new DecimalFormat("#.##");
    double d = 0.7750;
    System.out.println(" Double 0.7750 -> " +Double.valueOf(df.format(d)));
    float f = 0.7750f;
    System.out.println(" Float 0.7750f -> "+Float.valueOf(df.format(f)));
    // change the RoundingMode
    df.setRoundingMode(RoundingMode.HALF_UP);
    System.out.println(" Rounding Up Double 0.7750 -> " +Double.valueOf(df.format(d)));
    System.out.println(" Rounding Up Float 0.7750f -> " +Float.valueOf(df.format(f)));

Output:

Double 0.7750 -> 0.78
Float 0.7750f -> 0.77

Rounding Up Double 0.7750 -> 0.78
Rounding Up Float 0.7750f -> 0.77


public String getDecimalNumber(String number) {
        Double d=Double.parseDouble(number);
        return String.format("%.5f", d);
}

Take care of NumberFormatException as well


small simple program for demonstration:

import java.io.*;
import java.util.Scanner;

public class twovalues {

    public static void main(String args[]) {

        float a,b;
        Scanner sc=new Scanner(System.in);
        System.out.println("Enter Values For Calculation");

        a=sc.nextFloat();
        b=sc.nextFloat();

        float c=a/b;
        System.out.printf("%.2f",c);
    }
}


Just do String str = System.out.printf("%.2f", val).replace(",", "."); if you want to ensure that independently of the Locale of the user, you will always get / display a "." as decimal separator. This is a must if you don't want to make your program crash if you later do some kind of conversion like float f = Float.parseFloat(str);


Try this:-

private static String getDecimalFormat(double value) {

    String getValue = String.valueOf(value).split("[.]")[1];

      if (getValue.length() == 1) {
          return String.valueOf(value).split("[.]")[0] +
                "."+ getValue.substring(0, 1) + 
                String.format("%0"+1+"d", 0);
       } else {
          return String.valueOf(value).split("[.]")[0]
            +"." + getValue.substring(0, 2);
      }


 }
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