## 26.17 Sophisticated Captions

REVIEW Captions can be formatted quite extensively with a little knowledge of LaTeX. For Table ?? we illustrate generating a string in R that is passed through to the caption=. We use backports::paste() and base::Sys.time() and include some special symbols known to LaTeX as well as an occasion bold and italic font. Notice that because the caption is quite long we do not want the whole caption included in the list of tables in the contents pages. The second argument to caption= is the short title to use for the list of tables.

# Create a long caption as a single srting.

cpt <- paste("Here we include in the **caption**"
, "a sample of LaTeX symbols and formats"
, "that can be included in the string, and"
, "note that the caption string can be the"
, "result of R commands, using"
, "\paste() in this instance. Some"
, "sample symbols include: $\\alpha$"
, "$\\rightarrow$ $\\wp$."
, "We also get a timestamp from R:"
, Sys.time())

# Add the caption to the table.

dst %>%
xtable(digits=0
, caption=c(cpt, "Extended caption.")
, label="tblcap") %>%
print(include.rownames=FALSE)
% latex table generated in R 4.2.0 by xtable 1.8-4 package % Fri May 27 08:30:48 2022

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