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Formatting the floating point values

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Floating point Numbers can be formatted as a decimal number using String.format with 'f' flag 

//Two digits in fracttional part are rounded
String format1 = String.format("%.2f", 1.2399);
System.out.println(format1); // "1.24"

// three digits in fractional part are rounded 
String format2 = String.format("%.3f", 1.2399);
System.out.println(format2); // "1.240"

//rounded to two digits, filled with zero 
String format3 = String.format("%.2f", 1.2);
System.out.println(format3); // returns "1.20"

//rounder to two digits
String format4 = String.format("%.2f", 3.19999);
System.out.println(format4); // "3.20"

Floating point Numbers can be formatted as a decimal number using DecimalFormat 

// rounded with one digit fractional part 
 String format = new DecimalFormat("0.#").format(4.3200);
 System.out.println(format); // 4.3
 
// rounded with two digit fractional part 
 String format = new DecimalFormat("0.##").format(1.2323000);
 System.out.println(format); //1.23

 // formatting floating numbers to decimal number
 double dv = 123456789;
 System.out.println(dv); // 1.23456789E8
 String format =  new DecimalFormat("0").format(dv);
 System.out.println(format); //123456789
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Floating Point Operations:
* Java Floating Point Operations
* Comparing floating point values
* OverFlow and UnderFlow
* Formatting the floating point values
* Strict Adherence to the IEEE Specification
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124 java.util.Objects class
125 Java command: java and javaw
126 Atomic types
127 Floating Point Operations
128 Converting to and from strings
129 sun.misc.Unsafe
130 Java Memory Model
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184 Contributors