Composite Two questions: Column for Certain Tags & Chapter Numbers

[chicleeblair]

Hi,

I’m trying to clean up my library, specifically my tags, so that I can use them as shelves on BookFusion (and also so they’re just more easily navigable.) I have questions:

1. How do you build a composite column that populates with certain tags? For instance, if a book has the tags “Young Adult,” “Fiction” and “LGBT+” the new column would show “Young Adult” and “LGBT+”

2. Similar to the above, if I have books that have hierarchal tags like "Young Adult: Contemporary” and “Young Adult: Sci-Fi” can I limit the composite column to only show “Young Adult?”

I know I can do all of this with VL and saved searches, but if there’s a way to do with with templates I’d like to figure that out.

3. (Unrelated) Is there a way to populate a custom column with the number of chapters in an ePub? (One that’s not a fanfic).

[ownedbycats]

https://manual.calibre-ebook.com/template_lang.html

In particular, check out the various list functions. For #1, list_difference() can remove entries. Regexes are helpful here.

If it helps to see examples, here's an old version of my #subjects composite.

program:

tags = $tags;

	if 
		'^(Fiction|Nonfiction|Magazines & Publications)' in $#booktype 
	then 
## Split tags or return an empty
		split_tags = re(tags, '\.', ',') 
	else
		split_tags = ''
	fi;

## Removing a few unwanteds and sorting
	cleaned_tags = list_sort(list_difference(
		split_tags,
		'[Cleanup], Fiction, Nonfiction, Magazines & Publications, Cultures & Regions, Topics',
		','), 0, ',');

## Add 'Omnibus' if applicable
	if 
		'omnibus' 
	in 
		$#admintags 
	then 
		cleaned_tags  = 'Omnibus' & if cleaned_tags then ', ' & cleaned_tags fi
	fi;

	cleaned_tags

For #3, there really isn't a way to automatically count chapters and any method to do so would probably be fairly unreliable. I use 'Edit ToC' (a bit faster than opening the book), check there, and then manually input.

[chaley]

Originally Posted by chicleeblair

Hi,

2. Similar to the above, if I have books that have hierarchal tags like "Young Adult: Contemporary” and “Young Adult: Sci-Fi” can I limit the composite column to only show “Young Adult?”

If you are really using a colon as your hierarchical separator then life is more difficult. These tags aren't hierarchical in calibre. You must break them apart yourself using re() etc.

See this tutorial for how calibre supports hierarchical tags.

If instead you are using a period as the hierarchical separator then see the subitems() function.