The log method in JavaScript's Math object computes the natural logarithm of a specified number, utilizing base e. If the argument provided is a negative number, the method will yield NaN.
Syntax
The syntax for the log function is expressed as follows:
Example
Math.log(num)
Parameter
num - A number.
Return
The natural logarithm of a number.
JavaScript Math log method example
In this section, we will explore the log method by examining a range of examples.
Example 1
Let’s consider an example that demonstrates how to output the natural logarithm of a given number.
Example
<script>
document.writeln(Math.log(1)+"<br>");
document.writeln(Math.log(5)+"<br>");
document.writeln(Math.log(10));
</script>
Output:
Output
0
1.6094379124341003
2.302585092994046
Example 2
Let us examine the outcomes of the log function across various test scenarios.
Example
<script>
document.writeln(Math.log()+"<br>");
document.writeln(Math.log(-5)+"<br>");
document.writeln(Math.log(0));
</script>
Output:
Output
NaN
NaN
-Infinity
Example 3
In this section, you have the opportunity to evaluate the log method using your personalized test scenarios.
Example
<script>
function display()
{
var x=document.getElementById("num").value;
document.getElementById("result").innerHTML=Math.log(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>