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() Methodimport java.lang.*;Â Â public class Geeks {Â Â Â Â Â Â public static void main(String[] args)Â Â Â Â {Â Â Â Â Â Â Â Â Â Â // It will return 1 as long value is greater than 1Â Â Â Â Â Â Â Â System.out.println(Long.signum(36565531));Â Â Â Â Â Â Â Â Â Â // It will return -1 as long value is less than 1Â Â Â Â Â Â Â Â System.out.println(Long.signum(-628127));Â Â Â Â Â Â Â Â Â Â // Returns 0 as long value is equal to 0Â Â Â Â Â Â Â Â System.out.println(Long.signum(0));Â Â Â Â }} |
Output:
1 -1 0
Program 2: For decimal value and string.
// Java program to illustrate the// Java.lang.Long.signum() Methodimport 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
