arxiv categories order

[ErnestaP]

Fix arxiv categories order as it is in the original XML document. Current situation:

• article doi: 10.1103/PhysRevD.105.116011
• categories order:
  • "astro-ph.IM",
  • "hep-ph",
  • "hep-ex",
  • "astro-ph.HE"
• wanted order:
  • "hep-ph",
  • "astro-ph.HE",
  • "astro-ph.IM",
  • "hep-ex"

API to find categories: https://export.arxiv.org/api/query?search_query=id:{id_of_arxiv_eprints}

Solution: don't use a set in order to remove duplications in the array of categories. Duplications appears because primary category is repeated in the secondary categories list. l Instead of using set (which is unsorted), manually check for duplication and remove the element from the list using pop.

[drjova]

@ErnestaP could you please follow up with Anne?