Have the series number in the generated cover only when it is not zero

[halloleo]

The subtitle for generated book covers contains the Series name plus the Series number. This is acchive with the following template code:

{series:'test($, strcat("<i>", $, "</i> - ", raw_field("formatted_series_index")), "")'}

In some books I have set the series number to zero and then I only want the series name, but not the number in the sub title. - How can I achieve this on the book cover?

I looked for a "greater than" test in the Template Program Modesection of the doco, but couldn't figure it out...

[chaley]

Originally Posted by halloleo

I looked for a "greater than" test in the Template Program Modesection of the doco, but couldn't figure it out...

Use either the 'if' expression or the 'cmp' function.

[halloleo]

Thanks for chiming in @chaley!

I tried the "if" expression path, because I do not really need the numeric comparison, a string comparison against "0" should be enough.

However I get an error. The full code for my sub title expression looks like this:

{series:'test($, strcat("<i>", $, "</i>", program: if raw_field("formatted_series_index") == "0" then "" else raw_field("formatted_series_index"),"<br>"), "")'}
{#version:'test($, strcat("<b>", $, "</b>"),"")'}

and I always see the message "Template error Formatter" complaining about not enough closing brackets - but I think the brackets are correct. What do I do wromg?

[chaley]

There are several errors.

• The word "program:" is valid only at the beginning of a GPM template. You are using TPM so you don't need 'program'.
• You are missing the closing 'fi' for the 'if'.
• The raw_field() function returns 'None' for an undefined field. Because of that, comparing against the string "0" won't work. Numeric comparisons do work because the recognize "None" and change it internally to zero.

Here is a corrected version of your template, indented so I could read it.

{series:'
	test($,
		 strcat(
			"<i>",
			$,
			"</i>",
			if raw_field("formatted_series_index") ==# 0
				then ""
				else raw_field("formatted_series_index")
			fi,
			"<br>"),
		 "")'}
{#version:'test($, strcat("<b>", $, "</b>"),"")'}

Personally, I would use TPM for something this complicated. For example:

program:
	if $series then
		if $$#formatted_series_index ==# 0 then
			dex = ""
		else
			dex = $$#formatted_series_index
		fi;
		s = strcat("<i>", $series, "</i>", dex, "<br>")
	else
		s = ''
	fi;
	if $#version
	then
		v = strcat("<b>", $#version, "</b>")
	else
		v = ''
	fi;
	strcat(s, v)

I strongly suspect that you need a space after the > in "</i>"

[halloleo]

Thanks a lot @chaley!

That's great tip to convert the complete tetemplatee to TPM. I didn't know that's possible. It's soo much easier!

Basically I went with your TPM solution, I just made a few adjustments to your version to accommodate better my setup. For completeness I list that here:

program:
	if $series then
		if $$formatted_series_index == "0" then
			dex = ""
		else
			dex = strcat(" - ",$$formatted_series_index)
		fi;
		s = strcat("<i>", $series, "</i>", dex, "<br>")
	else
		s = ''
	fi;
	if $#version
	then
		v = strcat("<b>", $#version, "</b>")
	else
		v = ''
	fi;
	strcat(s, v)

Again, thanks a lot!

[chaley]

What is the lookup name "formatted_series_index"? There is no standard column with that name and it isn't a custom column because it is missing the leading '#'?

[halloleo]

I disagree (not that I'm a calibre expert): The default template for the subtitle was:

{series:'test($, strcat("<i>", $, "</i> - ", raw_field("formatted_series_index")), "")'}

So I understand formatted_series_index is a standard field related to series.

[chaley]

Originally Posted by halloleo

I disagree (not that I'm a calibre expert): The default template for the subtitle was:

{series:'test($, strcat("<i>", $, "</i> - ", raw_field("formatted_series_index")), "")'}

So I understand formatted_series_index is a standard field related to series.

For those who come across this thread later, the above is only partially true. The template is being evaluated in the context of generating a cover, which is the only place in calibre where the field "formatted_series_index" is valid.

[halloleo]

Originally Posted by chaley

The template is being evaluated in the context of generating a cover, which is the only place in calibre where the field "formatted_series_index" is valid.

Wow, this is very interesting! Didn't know it. Thanks @chaley.