You would have to supply the original filename, the pattern you used for the original filename and the pattern for the target filename.
If A1 is the %1 part, then $num(%1,1) will always return 0 as value.
You would have to supply the original filename, the pattern you used for the original filename and the pattern for the target filename.
If A1 is the %1 part, then $num(%1,1) will always return 0 as value.