A source file should have an attribute of PF-SRC
So first you would need to delete LF objects, then PF objects.
If there is on a single library or two, the easist way without doing any coding is using a User defined PDM option.
If you do WRKOBJPPDM xxxx where xxxx is your library name.
Then F16, here you can create a PDM option. Like DF DLTF &L/&N
Then F17 and use the filter option to get just the LF objects
Now put DF in the first subfile option
F13 to repeat to the end
Next go back and change your filter from LF to PF and repeat.