StrictMath scalb() Method in Java

1. The scalb(double num, int scale) is an inbuilt method of StrictMath class in Java which is used to calculate num * 2^scale and rounded as performed by a single correctly rounded floating point multiplied to a member of the double value argument.
   • The result is calculated accurately when the exponent of the result is between Double.MIN_EXPONENT and Double.MAX_EXPONENT.
   • An infinity is returned when the exponent of the result is greater than Double.MAX_EXPONENT.
   • When the result is subnormal then the correctness may be lost which means when scalb(num, scale) is subnormal, scalb(scalb(num, scale), -scale) may not equal num.
   • The result is NaN when the num is NaN
   • The result is an infinity of the same sign of num when num is infinite
   • The result will be a zero of the same sign when the num is zero.

   Syntax:

   public static double scalb(double num, int scale)

   Parameters: The method accepts two parameter:

   • num : This is of double type and refers to number to be scaled by a power of 2.
   • scalb : This is of integer type and refers to the power of 2 used to scale num.

   Return Value : The method returns the num × 2^scale.

   Examples :

   Input: num = 7
          scalb = 2
   Output: 28
   

   Below program illustrate the java.lang.StrictMath.scalb() method.

   // Java praogram to illustrate the
   // java.lang.StrictMath.scalb()
   import java.lang.*;
   
   public class Geeks {
   
   public static void main(String[] args) {
   
       double num1 = 12 , num2 = -7.2, num3 = 0.0;
       int scalb = 2;
   
       double scalb_Value = StrictMath.scalb(num1, scalb);
       System.out.println("Output = "+scalb_Value);
   
       scalb_Value = StrictMath.scalb(num2, scalb);
       System.out.println("Output = " +scalb_Value);
   
       scalb_Value = StrictMath.scalb(num3, scalb);
       System.out.println("Output = "+scalb_Value);
   }
   }
   Output:

   Output = 48.0
   Output = -28.8
   Output = 0.0
   

2. The scalb(float num, int scale) is the inbuilt method of StrictMath class in Java to calculate num * 2^scale and rounded as performed by a single correctly rounded floating point multiplied to a member of the float value argument.
   • The result is calculated accurately when the exponent of the result is between Float.MIN_EXPONENT and Float.MAX_EXPONENT.
   • An infinity is returned when the exponent of the result greater than Float.MAX_EXPONENT.
   • When the result is subnormal then the correctness may be lost which means when scalb(num, scale) is subnormal, scalb(scalb(num, scale), -scale) may not equal num.
   • The result is NaN when the num is NaN
   • The result is an infinity of the same sign of num when num is infinite
   • The result will be a zero of the same sign when the num is zero.

   Syntax :

   public static float scalb(float num, int scale)

   Parameters: The method accepts two parameter:

   • num : This is of float type and refers to number to be scaled by a power of 2.
   • scalb : This is of integer type and refers to the power of 2 used to scale num.

   Return Value : The method returns the num × 2^scale.

   Examples :

   Input: num = 2.5f
          scalb = 4
   Output: 40.0
   

   Below program illustrate the java.lang.StrictMath.scalb() method.

   // Java praogram to illustrate the
   // java.lang.StrictMath.scalb()
   import java.lang.*;
   
   public class Geeks {
   
   public static void main(String[] args) {
   
       float num1 = 8.3f, num2 = -4.2f, num3 = 0.0f;
       int scalb = 3;
   
       float scalb_Value = StrictMath.scalb(num1, scalb);
       System.out.println("Output = "+scalb_Value);
   
       scalb_Value = StrictMath.scalb(num2, scalb);
       System.out.println("Output = " +scalb_Value);
   
       scalb_Value = StrictMath.scalb(num3, scalb);
       System.out.println("Output = "+scalb_Value);
   }
   }
   Output:

   Output = 66.4
   Output = -33.6
   Output = 0.0