BigIntegerMath Class | Guava | Java

BigIntegerMath is used to perform mathematical operations on BigInteger values. Basic standalone math functions are divided into the classes IntMath, LongMath, DoubleMath, and BigIntegerMath based on the primary numeric type involved. These classes have parallel structure, but each supports only the relevant subset of functions. Similar functionality for int and for long can be found in IntMath and LongMath respectively.

Declaration : The declaration for com.google.common.math.BigIntegerMath class is :

@GwtCompatible(emulated = true)
public final class BigIntegerMath
   extends Object

Below table shows the methods provided by BigIntegerMath Class of Guava :

Exceptions :

• log2 : IllegalArgumentException if x <= 0
• log10 : IllegalArgumentException if x <= 0
• sqrt : IllegalArgumentException if x < 0
• divide : ArithmeticException if q == 0, or if mode == UNNECESSARY and a is not an integer multiple of b
• factorial : IllegalArgumentException if n < 0
• binomial : IllegalArgumentException if n < 0, k n

Example 1 :

// Java code to show implementation of
// BigIntegerMath Class of Guava
import java.math.*;
import com.google.common.math.BigIntegerMath;

class GFG {

    // Driver code
    public static void main(String args[])
    {

        // Creating an object of GFG class
        GFG obj = new GFG();

        // Function calling
        obj.examples();
    }

    private void examples()
    {

        try {

            // exception will be thrown as 10 is
            // not completely divisible by 3
            // thus rounding is required, and
            // RoundingMode is set as UNNESSARY
            System.out.println(BigIntegerMath.divide(BigInteger.TEN,
                                                new BigInteger("3"),
                                           RoundingMode.UNNECESSARY));
        }
        catch (ArithmeticException ex) {
            System.out.println("Error Message is : " +
                                       ex.getMessage());
        }
    }
}

Output:

Error Message is : Rounding necessary

Example 2 :

// Java code to show implementation of
// BigIntegerMath Class of Guava
import java.math.*;
import com.google.common.math.BigIntegerMath;

class GFG {

    // Driver code
    public static void main(String args[])
    {

        // Creating an object of GFG class
        GFG obj = new GFG();

        // Function calling
        obj.examples();
    }

    private void examples()
    {

        // As 10 is divisible by 5, so
        // no exception is thrown
        System.out.println(BigIntegerMath.divide(BigInteger.TEN,
                                        new BigInteger("5"),
                                    RoundingMode.UNNECESSARY));

        // To compute log to base 10
        System.out.println("Log10 is : " +
             BigIntegerMath.log10(new BigInteger("1000"),
                                 RoundingMode.HALF_EVEN));

        // To compute factorial
        System.out.println("factorial is : " +
                         BigIntegerMath.factorial(7));

        // To compute log to base 2
        System.out.println("Log2 is : " +
           BigIntegerMath.log2(new BigInteger("8"),
                          RoundingMode.HALF_EVEN));

        // To compute square root
        System.out.println("sqrt is : " +
                    BigIntegerMath.sqrt(BigInteger.
                    TEN.multiply(BigInteger.TEN),
                        RoundingMode.HALF_EVEN));
    }
}

Output:

2
Log10 is : 3
factorial is : 5040
Log2 is : 3
sqrt is : 10

Reference : Google Guava