# CADET-Process comparator.add\_difference\_metric() **URL:** \ **Category:** CADET Troubleshooting\ **Created:** [May 28, 2023, 5:00pm UTC](https://forum.cadet-web.de/t/cadet-process-comparator-add-difference-metric/699 "2023-05-28T17:00:48Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![ronald.jaepel](https://forum.cadet-web.de/user_avatar/forum.cadet-web.de/ronald.jaepel/32/986_2.png) [@ronald.jaepel](https://forum.cadet-web.de/u/ronald.jaepel)\ **Post date:** [May 28, 2023, 5:00pm UTC](https://forum.cadet-web.de/t/cadet-process-comparator-add-difference-metric/699/1 "2023-05-28T17:00:48Z")
Hello there, regarding CADET-Process comparator.add\_difference\_metric() method: Every example has (…, solution\_path=‘outlet.outlet’), which tries to use the whole outlet to compare against, i.e. all components returned at outlet.outlet. If I want to only compare against a single component of the outlet, how would I do that? Cheers, Ron ---
**Author:** ![ronald.jaepel](https://forum.cadet-web.de/user_avatar/forum.cadet-web.de/ronald.jaepel/32/986_2.png) [@ronald.jaepel](https://forum.cadet-web.de/u/ronald.jaepel)\ **Post date:** [May 28, 2023, 5:18pm UTC](https://forum.cadet-web.de/t/cadet-process-comparator-add-difference-metric/699/2 "2023-05-28T17:18:15Z")
Solved via text-message from @j.schmoelder : The difference metric constructor takes a components kwarg. So ``` comparator.add_difference_metric( ..., ..., 'outlet.outlet', components=["Protein X"] ) ``` solves the problem. ---
**Author:** ![ronald.jaepel](https://forum.cadet-web.de/user_avatar/forum.cadet-web.de/ronald.jaepel/32/986_2.png) [@ronald.jaepel](https://forum.cadet-web.de/u/ronald.jaepel)\ **Post date:** [May 28, 2023, 5:18pm UTC](https://forum.cadet-web.de/t/cadet-process-comparator-add-difference-metric/699/3 "2023-05-28T17:18:34Z")