I would like to know if it is easy or difficult to do the next thing:
I have a xhtml table, inside a form, where I have input values. I would like to have something similar to a spreadsheet, that when some input field is modified, some other fields are modified too. I'm using onkeyup(). But my problem is referencing the other fields because I haven't id attributes and the position of the nodes are different each time. Possibly this question is trivial, I'm new to Javascript, and any help or pointer in the right direction will be very useful.

Thanks very much.