Understanding the Feature-rich Methods of Math Package

The Math package is feature-rich and some of the methods are illustrated below.

public class MathPkg
{
public static void main(String args[])
{
MathPkg mathPkg = new MathPkg();
mathPkg.proceed();
}

private void proceed()
{
int positiveNum = 5;
int negativeNum = -5;

//Returns a double value 1.0 which implies it is positive (+)
System.out.println("Math.signum(" + positiveNum + "): " + Math.signum(positiveNum));
//Returns a double value -1.0 which implies it is negative (-)
System.out.println("Math.signum(" + negativeNum + "): " + Math.signum(negativeNum));

//Returns signOfSecondArgument with the firstArgument. So, here, it would result in -5.0
System.out.println("Math.copySign(" + positiveNum + "," + negativeNum + ")" + Math.copySign(positiveNum, negativeNum));

}
}

Expected output:

[root@mypc]# java MathPkg
Math.signum(5): 1.0
Math.signum(-5): -1.0
Math.copySign(5,-5)-5.0