Java中的长signum()方法
符号函数也称为符号函数,是一种提取实数符号的奇数数学函数。
Java.lang.Long.signum() 方法用于获取指定long值的signum函数。对于正值、负值和零,该方法分别返回 1、-1 和 0。
句法 :
public static int signum(long num)
参数:该方法接受一个长型参数num ,要对其执行signum操作。
返回值:该方法返回指定long值的signum函数。如果指定值为:
- 负数,该方法返回 -1。
- 零,该方法返回 0。
- 正,该方法返回 1。
例子:
Input: (Long) 2731766
Output: 1
Input: (Long) -233611
Output: -1
Input: (Long) 0
Output: 0
下面的程序说明了Java.lang.Long.signum() 方法:
方案一:
// 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));
}
}
输出:
1
-1
0
程序 2:用于十进制值和字符串。
// 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"));
}
}
输出:
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