I tried to add a formatter to my table columns that applies a new format to numeric cells. I used this #885 issue as a guide to my solution but it didn't seem to work.

Here's what I have:

`var column = oEvent.getSource().getParent().getParent().getLabel().getText();
var C = XLSX.utils.decode_col(column);
var fmt = "#,##0";
var range = XLSX.utils.decode_range(worksheet['!ref']);
for(var i = range.s.r + 1; i <= range.e.r; ++i) {
	 var ref = XLSX.utils.encode_cell({r:i, c:C});
	if(!worksheet[ref]) continue;
	if(worksheet[ref].t != 'n') continue;
	worksheet[ref].z = fmt;
}`

When I debug this code, I see that worksheet[ref] is "undefined". Even though ref itself is not undefined (e.g. it's "NIAYPRLSVBUYWS15") and my worksheet is also filled with the correct data.

Am I doing something wrong?
Thanks in advacne!

Note I'd like to apply that format AFTER the table has been rendered!