your original formula would also fail on a non numeric value as it is also using the
tonumber() function.
You have to decied what you want done with a non-numeric value. If you want to force tehm to the top of the sort then somethine like
if isnumeric({table.field}) then ToNumber({table.field}) else -1
You can use that for sorting (in the sort expert) and then use the original field for display on the report canvas.
if it is used in a grouping then suppress the group field and drop the original field on the group header for display
Edited by DBlank - 27 Oct 2014 at 8:19am