Javascript Math Reference : Math.random
Javascript Math.random
The Math.random takes does not take any argument and returns a random number between 0 and 1.
<html> <body> <script type="text/javascript"> <!-- /* ******************************************************** Example - Usage of Math.random ******************************************************** */ var x = Math.random(); // A random number between 0 and 1 document.writeln ("<br />Random Number between 0 and 1: " + x ); //--> </script> </body> </html> |
Try this example online here .
It is often required to find a random numeber between, say 0 to 10. How to do that ? All we do is multiply the returned result by 10 to get the random number between 0 and 10. Look at the following example which prints 10 random numbers between 0 and 10.
<html> <body> <script type="text/javascript"> <!-- /* ******************************************************** Example - Usage of Math.random ******************************************************** */ for (i=0; i<=9; i++) { x = Math.random()*10; document.writeln ("<br />Random Number between 0 and 10: " + x); } //--> </script> </body> </html> |
Try this example online here .
A typical output looks like
Random Number between 0 and 10: 7.743211425929848 Random Number between 0 and 10: 0.7056276518774696 Random Number between 0 and 10: 9.231555257045041 Random Number between 0 and 10: 0.33005140798325394 Random Number between 0 and 10: 7.22913748778844 Random Number between 0 and 10: 2.847247377972332 Random Number between 0 and 10: 9.219032827412834 Random Number between 0 and 10: 5.978896927307241 Random Number between 0 and 10: 8.50390484138096 Random Number between 0 and 10: 1.4229072921192354
You could potentiall use the round function if you do not like the decimal places as in
x = Math.round(Math.random()*10);
Try making the above change to see the result.