Javascript - Math
The Math object allows you to perform mathematical tasks.
round()
How to use round
<html>
<body>
<script type="text/javascript">
document.write(Math.round(0.60) + "<br />");
document.write(Math.round(0.50) + "<br />");
document.write(Math.round(0.49) + "<br />");
document.write(Math.round(-4.40) + "<br />");
document.write(Math.round(-4.60));
</script>
<body>
<html>
random()
How to use a random() to return a random number between 0 and 1.
<html>
<body>
<script type="text/javascript">
//return a random number between 0 and 1
document.write(Math.random() + "<br />");
//return a random integer between 0 and 10
document.write(Math.floor(Math.random()*11));
</script>
</body>
</html>
max()
How to use max() to return the number with the highest value of two specified numbers.
<html>
<body>
<script type="text/javascript">
document.write(Math.max(5,10) + "<br />");
document.write(Math.max(0,150,30,20,38) + "<br />");
document.write(Math.max(-5,10) + "<br />");
document.write(Math.max(-5,-10) + "<br />");
document.write(Math.max(1.5,2.5));
</script>
</body>
</html>
min()
How to use min() to return the number with the lowest value of two specified numbers.
<html>
<body>
<script type="text/javascript">
document.write(Math.min(5,10) + "<br />");
document.write(Math.min(0,150,30,20,38) + "<br />");
document.write(Math.min(-5,10) + "<br />");
document.write(Math.min(-5,-10) + "<br />");
document.write(Math.min(1.5,2.5));
</script>
</body>
</html>
The Math object allows you to perform mathematical tasks. The Math object includes several mathematical constants and methods.
Syntax for using properties/methods of Math:
var x=Math.PI;
var y=Math.sqrt(16);
Note: Math is not a constructor. All properties and methods of Math can be called by using Math as an object without creating it.
JavaScript provides eight mathematical constants that can be accessed from the Math object. These are: E, PI, square root of 2, square root of 1/2, natural log of 2, natural log of 10, base-2 log of E, and base-10 log of E.
You may reference these constants from your JavaScript like this:
Math.E
Math.PI
Math.SQRT2
Math.SQRT1_2
Math.LN2
Math.LN10
Math.LOG2E
Math.LOG10E
In addition to the mathematical constants that can be accessed from the Math object there are also several methods available.
The following example uses the round() method of the Math object to round a number to the nearest integer:
document.write(Math.round(4.7));
The code above will result in the following output:
5
The following example uses the random() method of the Math object to return a random number between 0 and 1:
document.write(Math.random());
The code above can result in the following output:
0.9783056710041675
The following example uses the floor() and random() methods of the Math object to return a random number between 0 and 10:
document.write(Math.floor(Math.random()*11));
The code above can result in the following output:
9