# Long signum() Method in Java

The signum function also known as sign function is an odd mathematical function that extracts the sign of a real number.
The java.lang.Long.signum() method is used to get the signum function of the specified long value. For a positive value, a negative value and zero, the method returns 1, -1 and 0 respectively.

Syntax :

`public static int signum(long num)`

Parameters: The method accepts one parameter num of long type on which the signum operation is to be performed.

Return Value: The method returns the signum function of the specified long value. If the specified value is:

• Negative, the method returns -1.
• Zero, the method returns 0.
• Positive, the method returns 1.

Examples:

```Input: (Long) 2731766
Output: 1

Input: (Long) -233611
Output: -1

Input: (Long) 0
Output: 0
```

Below programs illustrate the Java.lang.Long.signum() Method:
Program 1:

 `// Java program to illustrate the ` `// Java.lang.Long.signum() Method ` `import` `java.lang.*; ` ` `  `public` `class` `Geeks { ` ` `  `    ``public` `static` `void` `main(String[] args) ` `    ``{ ` ` `  `        ``// It will return 1 as long value is greater than 1 ` `        ``System.out.println(Long.signum(``36565531``)); ` ` `  `        ``// It will return -1 as long value is less than 1 ` `        ``System.out.println(Long.signum(-``628127``)); ` ` `  `        ``// Returns 0 as long value is equal to 0 ` `        ``System.out.println(Long.signum(``0``)); ` `    ``} ` `} `

Output:

```1
-1
0
```

Program 2: For decimal value and string.

 `// Java program to illustrate the ` `// Java.lang.Long.signum() Method ` `import` `java.lang.*; ` ` `  `public` `class` `Geeks { ` ` `  `    ``public` `static` `void` `main(String[] args) ` `    ``{ ` ` `  `        ``// It will return compile time error ` `        ``System.out.println(Long.signum(``36565.531``)); ` ` `  `        ``// It will return compile time error ` `        ``System.out.println(Long.signum(``"628127"``)); ` `    ``} ` `} `

Output:

```
prog.java:10: error: incompatible types: possible lossy conversion from double to long
System.out.println(Long.signum(36565.531));
^
prog.java:13: error: incompatible types: String cannot be converted to long
System.out.println(Long.signum("628127"));
^
Note: Some messages have been simplified; recompile with -Xdiags:verbose to get full output
2 errors
```

My Personal Notes arrow_drop_up

lets make it a lil simple

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