How to validate a value entered into an input field and return a value to the input field?

Glyndwr

http://live.datatables.net/wurejodu/1/edit

When the user enters a value into an <input> field I would like to validate the input amount. If it is lowercase 'i' or 'e' return uppercase ('I' or 'E') to the input field; otherwise, return blank to the input field.

Glyndwr

I have removed the "parseFloat()".