Java sqrt()用法及代码示例

java.lang.Math.sqrt()返回作为参数传递给它的double类型值的平方根。如果参数为NaN或负数，则结果为NaN。如果参数为正无穷大，则结果为正无穷大。如果传递的参数为正零或负零，则结果将与参数相同。

用法：

public static double sqrt(double a)
Parameter:
a:the value whose square root is to be returned.
Return:
This method returns the positive square root value of 
the argument passed to it.

例子1：显示java.lang.Math.sqrt()方法的用法。

// Java program to demonstrate working 
// of java.lang.Math.sqrt() method 
import java.lang.Math; 
  
class Gfg { 
  
    // driver code 
    public static void main(String args[]) 
    { 
        double a = 30; 
  
        System.out.println(Math.sqrt(a)); 
  
        a = 45; 
  
        System.out.println(Math.sqrt(a)); 
  
        a = 60; 
  
        System.out.println(Math.sqrt(a)); 
  
        a = 90; 
  
        System.out.println(Math.sqrt(a)); 
    } 
}

输出：

5.477225575051661
6.708203932499369
7.745966692414834
9.486832980505138

例子2：当参数为NaN或+ infinity时，显示java.lang.Math.sqrt()方法的用法。

// Java program to demonstrate working 
// of java.lang.Math.sqrt() method 
import java.lang.Math; // importing java.lang package 
  
public class GFG { 
    public static void main(String[] args) 
    { 
  
        double positiveInfinity = Double.POSITIVE_INFINITY; 
        double negativeVal = -5; 
        double nan = Double.NaN; 
        double result; 
  
        // Here argument is negative, 
        // output will be NaN 
        result = Math.sqrt(negativeVal); 
        System.out.println(result); 
  
        // Here argument is positive infinity, 
        // output will also positive infinity 
        result = Math.sqrt(positiveInfinity); 
        System.out.println(result); 
  
        // Here argument is NaN, output will be NaN 
        result = Math.sqrt(nan); 
        System.out.println(result); 
    } 
}

输出：

NaN
Infinity
NaN

相关用法

注：本文由纯净天空筛选整理自barykrg大神的英文原创作品 Java sqrt() method with Examples。非经特殊声明，原始代码版权归原作者所有，本译文未经允许或授权，请勿转载或复制。