The JavaScript Math.sign function provides the sign of a specified number. It reveals whether the input number is positive, negative, or equals zero.
Syntax
The syntax for the sign method is expressed as follows:
Example
Math.sign(num)
Parameter
num - A number.
Return
The sign of the given number.
JavaScript Math sign method example
In this section, we will explore the sign method by examining a range of examples.
Example 1
Let’s examine an illustration to determine the sign of the specified number.
Example
<script>
document.writeln(Math.sign(12)+"<br>");
document.writeln(Math.sign(-12)+"<br>");
document.writeln(Math.sign(0));
</script>
Output:
Output
1
-1
0
Example 2
Let’s examine a few scenarios in which the sign function yields NaN.
Example
<script>
document.writeln(Math.sign(NaN)+"<br>");
document.writeln(Math.sign("string")+"<br>");
document.writeln(Math.sign());
</script>
Output:
Output
NaN
NaN
NaN
Example 3
In this section, you have the opportunity to evaluate the sign method using your own test scenarios.
Example
<script>
function display()
{
var x=document.getElementById("num").value;
document.getElementById("result").innerHTML=Math.sign(x);
}
</script>
<form>
Enter a number: <input type="text" id="num">
<input type="button" onclick="display()" value="submit">
</form>
<p><span id="result"></span></p>