爪哇番石榴| LongMath.divide(长、长、圆模式)方法示例

原文:https://www . geesforgeks . org/Java-guava-long math-dividelong-long-rounding-mode-method-with-examples/

番石榴龙数学类除法(长 p,长 q,舍入模式)方法接受三个参数,计算第一个参数除以第二个参数的结果,根据第三个参数指定的舍入模式进行舍入。

语法:

public static long divide(long p,
                          long q,
                          RoundingMode mode)

参数:该方法取 3 个参数,其中 pq 为长整型, 模式 为指定的舍入模式。

返回值:该方法返回第一个参数除以第二个参数,根据第三个参数指定的舍入方式进行舍入。

异常:方法抛出 算法异常 如果:

  • Q == 0, or
  • Pattern = = unnecessary and p is not an integer multiple of Q.

枚举舍入模式

| 枚举常数 | 描述 | | 【天花板】 | 舍入模式向正无穷大舍入。 | | DOWN | 舍入模式为向零舍入。 | | FLOOR | 舍入模式为向负无穷大舍入。 | | HALF _ DOWN | 舍入模式为向“最近邻居”舍入,除非两个邻居等距,在这种情况下舍入为 DOWN。 | | HALF _ EVEN | 舍入模式为向“最近邻居”舍入,除非两个邻居等距,在这种情况下,向偶数邻居舍入。 | | 【HALF _ UP】 | 取整模式为向“最近邻居”取整,除非两个邻居等距,在这种情况下取整。 | | 【不必要的】 | 舍入模式断言请求的操作有确切的结果,因此没有舍入的必要。 | | UP | 取整模式为远离零取整。 |

下面的例子说明了上述方法的实现:

例 1 :

// Java code to show implementation of
// divide(long p, long q, RoundingMode mode)
// method of Guava's LongMath class

import java.math.RoundingMode;
import com.google.common.math.LongMath;

class GFG {

    // Driver code
    public static void main(String args[])
    {
        long dividend1 = 55;
        long divisor1 = 10;

        // Using divide(long p, long q,
        // RoundingMode mode)
        // method of Guava's LongMath class
        long quotient1
            = LongMath.divide(dividend1, divisor1,
                              RoundingMode.HALF_DOWN);

        System.out.println(quotient1);

        long dividend2 = 55;
        long divisor2 = 10;

        // Using divide(long p, long q,
        // RoundingMode mode)
        // method of Guava's LongMath class
        long quotient2
            = LongMath.divide(dividend2, divisor2,
                              RoundingMode.CEILING);

        System.out.println(quotient2);
    }
}

输出:

5
6

例 2 :

// Java code to show implementation of
// divide(long p, long q, RoundingMode mode)
// method of Guava's LongMath class

import java.math.RoundingMode;
import com.google.common.math.LongMath;

class GFG {

    static long findDiv(long dividend,
                        long divisor,
                        RoundingMode mode)
    {
        try {
            // Using divide(long p, long q,
            // RoundingMode mode)
            // method of Guava's LongMath class
            long quotient
                = LongMath.divide(dividend,
                                  divisor,
                                  RoundingMode.HALF_DOWN);

            // Return the answer
            return quotient;
        }
        catch (Exception e) {
            System.out.println(e);
            return -1;
        }
    }

    // Driver code
    public static void main(String args[])
    {
        long dividend = 32;
        long divisor = 0;

        try {

            // Function calling
            findDiv(dividend, divisor,
                    RoundingMode.HALF_EVEN);
        }
        catch (Exception e) {
            System.out.println(e);
        }
    }
}

输出:

java.lang.ArithmeticException: / by zero

参考:https://Google . github . io/guava/releases/20.0/API/docs/com/Google/common/math/longmath . html # divide-long-long-Java . math . round ingmode-