Assignment

Hi all, I am sorting out the problem to allow decimal field in grade.http://tracker.moodle.org/browse/MDL-20368 I need a java script that will validate the text box to allow the decimal fields like 100, 99.5, 10.05, 0.1, 23.10 etc Until now I searched a lot how to create the java script in Moodle but got confusion in YUI and java scripts. Problem Statement: How to create a java script (function) which will validate the text box on each keystroke to allow decimal field as stated above. My work ..... Until now, for backend, I have created a php regular expression that will validate any input form that text box to allow only decimal numbers but for the front end, I am thinking about to have a java script for validation of input text, that will be really helpful for user what to enter and what not to?. I am new to java scripts. If you have any ideas, please post it here, that wiil be very useful for next steps. Thanks.......