I have a portal which is sorted by a calculation field set from a global field via a script button using a Case statement.

This is fine for sorting ascending but I cant figure out how to sort the portal for a text field in descending order.

Number fields are ok - just use 1/(field value)

But How do I get a text field to populate the sort field in descending order for a text field.

Thanks

You can't populate a field in descending order (nice trick with the numbers though).

How about a numeric to represent the first character of the text and use the numeric as your sort key, and apply the 1/n trick. If you can think in BASE-26 then you could get quite an accurate alpha-numeric conversion by extending into the following characters.