Okay DigiPresHiveMind, I have a question... I have a big pile of MARC XML. I don't know MARC, so unlike the experts I've worked with, I can't expand all these letters and codes in my head! Is there a library that will do some basic expansion of MARC into something I can understand? I realise this might be lossy, but some kind of Dublin Core or plain-old-CSV projection would be helpful!
Writing that made me realised XSLT exists, and I managed to find https://www.loc.gov/standards/marcxml/xslt/MARC21slim2RDFDC.xsl but not really any official looking documentation about it?
Ah, okay, DC in RDF. Now I have two problems... ;-) https://www.loc.gov/standards/marcxml/
(there is also some METS for every MARC...)
Looking at pymarc, it seems like this'll do: "A pymarc.Record object has a few handy properties like title for getting at bits of a bibliographic record, others include: author, isbn, subjects, location, notes, physicaldescription, publisher, pubyear." (It goes on to warn that this is missing a lot of detail, but I can live with that for this purpose).
@anj if you feel the need for speed you could try the new mrrc here too, since it has similar helper methods and is python wrapped rust. Although it is still being tested...
@anj well, I struggled many times doing this and none of the libraries I have used https://github.com/knakk/kbp https://github.com/miku/marc21 does a code translation to a human vocabulary.
The best resource I use to understand those codes is this old unmaintained wiki http://unimarc-it.wikidot.com/ (italian only, unkown maintainer)
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@anj as a fellow non-MARC understander, this thread is cursed 😱
@anj As someone who also doesn't do MARC but is fresh off a pair of library school metadata classesβ€”if you can find something to convert it to MODS, it will be fairly readable, and I believe such converters exist.
Online Bibliographic Metadata Tools

Free Online file conversion. Convert bibliographic metadata formats. Support for large file conversions.

@linguistory @anj I would also recommend MarcEdit for transformations and also just for looking at files if you want to start to see patterns. You can also export a subset of fields into a tab-separated value, which I find extremely helpful.

There are also some built-in transforms.

If you want reference, I recc: https://www.loc.gov/marc/bibliographic/index.html

Looking at other stuff in the thread pymarc's labeled fields are definitely helpful for just getting some basics out of each, which MarcEdit doesn't support.