StrictMath scalb() Method in Java

• 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.

public static double scalb(double num, int scale)

• 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.

Input: num = 7
       scalb = 2
Output: 28

// 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 = 48.0
Output = -28.8
Output = 0.0

• 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.

public static float scalb(float num, int scale)

• 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.

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

// 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 = 66.4
Output = -33.6
Output = 0.0