I have a "Radio Button element" (bi-era.com-listbox is the name of the extension) that allows me to select a list of dimensions. The table has two dimensions: Data and Dim1 that is a varaiable and changes depending on the item selection.
I attached an image that shows the table and the Radio Box Element:
In the table properties, in added
"Data" in "Rows" section,
"Dim1" in "Columns" section with this expression $(='[' & only(Dim1) & ']') because It's possible to change the dimension analysis by the Radio Button element
And I added a misure too.
Dim1 is so defined:
Load * Inline [
'Dimension W', 'www'
So, I tried to write the expression that you suggested, in this way: