Java Guava | LongMath log10(long x, RoundingMode mode) method with Examples

The method log10(long x, RoundingMode mode) of Guava’s LongMath Class accepts two parameters and calculates the base-10 logarithmic value of the first parameter rounded according to the rounding mode specified by the second parameter.

Syntax:

public static int log10(long x, RoundingMode mode)

Parameters: The method takes 2 parameters:

• x is the long value to be found log of.
• mode is the specified rounding mode.

Return Value: This method returns Base-10 logarithm of x, rounded according to the specified rounding mode.

Exceptions: This method throws following parameters:

• IllegalArgumentException: if the value x is 0 or a negative value.
• ArithmeticException: if mode is RoundingMode.UNNECESSARY and x is not a power of ten.

Enum RoundingMode

Enum Constant Description
CEILING Rounding mode to round towards positive infinity.
DOWN Rounding mode to round towards zero.
FLOOR Rounding mode to round towards negative infinity.
HALF_DOWN Rounding mode to round towards “nearest neighbor” unless both neighbors are equidistant, in which case round down.
HALF_EVEN Rounding mode to round towards the “nearest neighbor” unless both neighbors are equidistant, in which case, round towards the even neighbor.
HALF_UP Rounding mode to round towards “nearest neighbor” unless both neighbors are equidistant, in which case round up.
UNNECESSARY Rounding mode to assert that the requested operation has an exact result, hence no rounding is necessary.
UP Rounding mode to round away from zero.

Below given are some examples to understand the implementation in a better way:

Example 1:

 // Java code to show implementation of // log10(long x, 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 a1 = 10000;            // Using log10(long x, RoundingMode mode)         // method of Guava's LongMath class         // The RoundingMode HALF_EVEN rounds towards         // the "nearest neighbor" unless both neighbors         // are equidistant, in which case, round towards         // the even neighbor.         System.out.println(             LongMath.log10(                 a1,                 RoundingMode.HALF_EVEN));            long a2 = 15;            // Using log10(long x, RoundingMode mode)         // method of Guava's LongMath class         // The RoundingMode HALF_DOWN rounds towards         // "nearest neighbor" unless both neighbors         // are equidistant, in which case round down.         System.out.println(             LongMath.log10(a2,                            RoundingMode.HALF_DOWN));     } }

Output :

4
1

Example 2 :

 // Java code to show implementation of // log10(long x, RoundingMode mode) method // of Guava's LongMath class    import java.math.RoundingMode; import com.google.common.math.LongMath;    class GFG {        static int findlog10(long x, RoundingMode mode)     {         try {             // Using log10(long x, RoundingMode mode)             // method of Guava's LongMath class             // The RoundingMode HALF_EVEN rounds towards             // the "nearest neighbor" unless both neighbors             // are equidistant, in which case, round towards             // the even neighbor.             // This should throw "IllegalArgumentException"             // as x <= 0             int ans = LongMath.log10(x, mode);                // Return the answer             return ans;         }         catch (Exception e) {             System.out.println(e);             return -1;         }     }        // Driver code     public static void main(String args[])     {         long x = -122;            try {                // Function calling             findlog10(x, RoundingMode.HALF_EVEN);         }         catch (Exception e) {             System.out.println(e);         }     } }

Output :

java.lang.IllegalArgumentException: x (-122) must be > 0

My Personal Notes arrow_drop_up In love with a semicolon because sometimes i miss it so badly)

If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

Please Improve this article if you find anything incorrect by clicking on the "Improve Article" button below.

Article Tags :
Practice Tags :

Be the First to upvote.

Please write to us at contribute@geeksforgeeks.org to report any issue with the above content.