xgen table row/column position

Is there a way in an xgen script to get the values of the subscripts
for the current cell (i.e. row and column position) of a table.

I'd like to click on a cell in the table, then click on a button and
have some data automatically written into that cell. But I need a way
to know what subscripts to use in order to write into the table array.

Thanks for any hints.

- Bob (black@calspan.com)