If ... Then in custom column

[Marco24]

Hi all,

First, sorry if this thread is a duplicate. I've made some research and I did not find any helpful topics regarding my skills in calibre customization ;p

I would like to create custom columns that tells me if some custom metadata are missing or not.
Data quality check plugin is not relevant in this case.

example of check I want to realize :
1rst example :
if #genre contains SF or Fantasy or Weird then populate the column with SFFF else empty

I've tried with the first test but it doesn't work
{#genre:contains('SF','SFFF',{null})}

another example of test I want to realize :
if #nationalite not in (fr, ca) and #translator is null and #VO-title is null
then #customcolumn = "translation data missing"
else empty

I've tried different method but none of them actually works
I suppose that I'm missing something important ;p

thanks in advance

[Gary_M_Mugford]

Marco,

This is just a quickie off the top of my head, so, experiment first and if it doesn't go as I indicate, I apologize for wasting your time.

I'd try {#genre:contains('SF','SFFF',''} (that's TWO SINGLE QUOTES typed without a space). Now, you can STACK the test. {#genre:contains('SF','SFFF',{#genre:contains('MYS ','MYS&THR'}} if you want, but be careful. I'd start in a text editor and then make sure my brackets were there as you compose a seriously compound test for a custom column. When you have that all looking right, THEN I'd work on a copy, delete all carriage returns and extraneous spaces and use that to test. (just some experience talking)

The key is that Null doesn't seem to be useful to what you are trying to do in terms of returned result. But I could be wrong. It's forever since CHaley guided my way through the template language for plugboards and custom columns.

Now, if you want a compound RESULTS column, where it can be SFFF AND MYS&THR, then you have to sequentially run each test and add to the result when you get each positive. That's a program, which Calibre can do. I'll leave you to look it up.

Hope that helps a little, GM

[chaley]

Originally Posted by Marco24

1rst example :
if #genre contains SF or Fantasy or Weird then populate the column with SFFF else empty

Try this General Program Mode template:

program:
	test(list_intersection('SF, Fantasy, Weird', field('#genre'), ','), 'SFFF', '')

another example of test I want to realize :
if #nationalite not in (fr, ca) and #translator is null and #VO-title is null
then #customcolumn = "translation data missing"
else empty

program:
	test(
		strcat(
			list_intersection('fr, ca', field('#nationalite'), ','),
			field('#translator'),
			field('#VO-title')
		), 
	'', 'translation data missing')

NB: I can't test this template because I don't have the three columns it references.

The template produces output only if the three expressions produce an empty value, determined by concatenating the results of the three expressions.

• The first, the list_intersection, produces a non-empty value if the field contains one of the two nationalities.
• The second produces a non-empty value if #translator contains a value.
• The second produces a non-empty value if #VO-title contain a value.

If the strcat is non-empty (any of the expressions returned a value) then the test produces empty.

In effect, the template implements your expression altered using De Morgan's Laws

if not (#nationalite in (fr, ca) or #translator is not null or #VO-title is not null)
then "translation data missing"
else empty

[Gary_M_Mugford]

Good to see you stepping into my breech, sir. Marco is in good hands. GM

[Marco24]

Hi Gary and Charles

thanks a lot for your help.
I used the General Program Mode as described by Gary and it works.
Thanks to you, I know now how to program 'if... then... else...' using test(...) and list_intersection(...)

[Gary_M_Mugford]

Actually Marco, it was Chaley to the rescue. He's THE Man when it comes to this kind of stuff. He helped me eons ago and continues to help others. I appreciate being thanked for my small effort here, but the man to thank specifically is Chaley. GM