check if a number is positive or negative javascript code example

Example 1: check if number is negative javascript

const positive = 5;
const negative = -5;
const zero = 0;

Math.sign(positive); // 1
Math.sign(negative); // -1
Math.sign(zero); // 0

Example 2: check if number is negative javascript

Math.sign() has 5 possible return values:
1 // positive number
-1 // negative number
0 // positive zero
-0 // negative zero
NaN // not a number

Example 3: Check if a Number is Positive or Negative using if else

public class PositiveNegative {

    public static void main(String[] args) {

        double number = 12.3;

        // true if number is less than 0
        if (number < 0.0)
            System.out.println(number + " is a negative number.");

        // true if number is greater than 0
        else if ( number > 0.0)
            System.out.println(number + " is a positive number.");

        // if both test expression is evaluated to false
        else
            System.out.println(number + " is 0.");
    }
}