Introduce longtabu example

With some juicy (and equally useless) Lua code

chapters/backmatter.tex

@@ -15,6 +15,51 @@ \section{More appendix}
 
 \Blindtext
 
+\section{Unprocessed data}
+\label{ch:appendix_table}
+
+This is also a good place to put unprocessed data, like \cref{tab:random_long}.
+
+% All following long tables will have the following setting, which could make sense for
+% the appendix.
+\AtBeginEnvironment{longtabu}{\footnotesize}{}{}
+
+\begin{longtabu}{%
+ % ATTENTION: the `tabu` package is unmaintained and a bunch of stuff doesn't work.
+ % See also https://github.com/tabu-issues-for-future-maintainer/tabu.
+ % Pretty bad situation but works okay enough, and we already use `tabu`/`longtable`
+ % anyway for the glossaries in `glossaries-extra`.
+ %
+ @{}% Remove superfluous left horizontal space
+ % NOTE: `X[c]{S}` columns, like in the `tabu` docs, do not really work, see also
+ % https://tex.stackexchange.com/q/70279/120853
+ S% `S` expects what `\num` would: a number
+ s% `s` expects what `\si` would: a unit
+ X[2, l]% double the width factor when computing automatic widths
+ X[1, l, $]% Dollar sign breaks my editor's syntax highlighting
+ @{}% Remove superfluous right horizontal space
+}%
+ \caption[A \texttt{longtable} from the \ctanpackage{tabu} package]{
+ A \texttt{longtable} from the \ctanpackage{tabu} package.
+ It can break across pages but still have a caption.
+ The \ctanpackage{tabu} package allows automatic width scaling:
+ the table is as wide as the text automatically (which sometimes looks bad).
+ There are also automatic numbers (note the horizontal decimal point alignment), units (also from \ctanpackage{siunitx}, not \ctanpackage{tabu}) and math columns.
+ Note how the table rows are generated automatically and randomly, using Lua%
+ \label{tab:random_long}%
+ }\\
+ \toprule
+ Magnitude & Unit & Double-width text & \text{Math column} \\
+ \midrule
+ 118.135 & \nano\meter & Foo & f-x=h\\
+ % The following rows look just like that but are generated:
+ \directlua{%
+ N_ROWS = 75
+ dofile("lib/lua/generate_random_table_rows.lua")
+ }
+ \bottomrule
+\end{longtabu}
+
 \chapter{Another appendix chapter}
 
 More stuff can go into the next appendix chapter, for example algorithms and code.

chapters/mainmatter/floats.tex

@@ -444,6 +444,10 @@ \subsubsection{Large Floats}
  \end{table}%
 \end{landscape}
 
+\paragraph{Very long tables}
+
+See \cref{tab:random_long} in \cref{ch:appendix_table} for an example of a very large table (which does not float).
+
 \subsubsection{Table Style}
 
 In general, use the least ink possible to get your point across.

lib/lua/generate_random_table_rows.lua

@@ -0,0 +1,77 @@
+--[[
+ The following import is not required since in LuaTeX's `\directlua` environment,
+ `texio` etc. is already available. However, this is nice to keep linters from
+ complaining about an undefined variable.
+--]]
+local texio = require("texio")
+local tex = require("tex")
+
+PREFIXES = {"", "kilo", "milli", "giga", "nano"}
+
+UNITS = {"meter", "degreeCelsius", "kelvin", "gram", "bar", "pascal", "newton", "candela", "ampere", "ohm", "volt",
+ "watt"}
+
+TEXTS = {"This is a longer text that will probably span multiple lines in the table because it is overly wide.",
+ "Hello World", "A", "B", "C", "Foo", "Bar", "Baz", "Yeet"}
+
+MATH_OPS = {"+", "-", "/", "^"}
+MATH_SYMBOLS = {"a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u",
+ "v", "w", "x", "y", "z", "A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M", "N", "O", "P",
+ "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z"}
+
+-- Seed with `os.time()` for true randomness; keep a constant seed for
+-- reproducibility:
+RANDOM_SEED = RANDOM_SEED or os.time()
+math.randomseed(RANDOM_SEED)
+
+local function choice(table)
+ -- Imitating Python's `random.choice` to pick a random element from a table.
+ return table[math.random(#table)]
+end
+
+local function random_int(n_digits)
+ -- Returns a random integer with the specified number of digits
+ if n_digits < 1 then
+ -- `min` can be `0 <= min <= 1` from e.g. 10^(0 - 1), which cannot be fed to
+ -- `math.random` properly, so return early here.
+ return 0
+ end
+
+ local min = 10 ^ (n_digits - 1) -- e.g. 2 -> 10
+ local max = (10 ^ n_digits) - 1 -- e.g. 2 -> 100 - 1 -> 99
+ return math.random(min, max)
+end
+
+local function latex_table_row()
+ local max_n_digits_left, max_n_digits_right = 3, 3
+ local n_digits_left = math.random(0, max_n_digits_left)
+ local n_digits_right = math.random(0, max_n_digits_right)
+ local left, right = random_int(n_digits_left), random_int(n_digits_right)
+ -- We could do some super cool bit logic to achieve the desired floating decimal
+ -- points but I'm not smart enough, so cast to string like a monkey.
+ local number = left .. "." .. right
+
+ local prefix = choice(PREFIXES)
+ if prefix ~= "" then
+ -- Do not allow `\\` to pass, aka prefix is empty string
+ prefix = "\\" .. prefix
+ end
+ local unit = "\\" .. choice(UNITS)
+
+ local text = choice(TEXTS)
+
+ local math = choice(MATH_SYMBOLS) .. choice(MATH_OPS) .. choice(MATH_SYMBOLS) .. "=" .. choice(MATH_SYMBOLS)
+
+ local row_eol = "\\\\"
+ local column_sep = " & "
+ local row = table.concat({number, prefix .. unit, text, math}, column_sep) .. row_eol
+ texio.write_nl("Generated new table row: " .. row)
+ return row
+end
+
+-- See if defined, else fallback to default:
+N_ROWS = N_ROWS or 75
+
+for _ = 1, N_ROWS do
+ tex.print(latex_table_row())
+end