Guidelines for Rd files

• The page \title and the \section titles should be capitalized and not end in a period.
  It is best to avoid all markup in titles, which need to be automatically processed for various hypertext search systems.
• Argument lists need to cover all the arguments in all the functions covered, including '...'.
  This is also checked by tools::checkDocFiles(), run as part of R CMD check.
• Do provide text alternatives for all but the very simplest \eqn and \deqn commands.
• In \source and \references sections
  • Use separate paragraphs (separated by a blank line) for each reference.
  • Write authors' names in the form Author, A. B. and separate them by a comma or and (but not both).
  • Give a date immediately after the author(s), and do not put a period after the date.
  • Enclose titles of books and journals (but not articles) in \emph{...}.
  • Enclose volume numbers for journals in \bold{...} and follow them by a comma.
  • Use -- for page ranges.
  • If you give an address for a publisher (probably unnecessary) use the form New York: Springer-Verlag.
• In \usage and \examples sections
  • Watch the line length: 65 characters is a reasonable limit.
  • Use TRUE and FALSE rather than T and F.
  • Readability is greatly enhanced by adding spaces around binary operators and after commas in argument lists. In particular, <- needs spaces around it.
  • Always use <- rather than = for assignments.
  • Follow the 'R core' indentation guidelines for example code (which basically means an indentation level of 4 spaces and aligning continuation lines suitably — but copy the code into a .R Emacs buffer and reformat it there).
• Ensure that the \usage section exactly matches the function definition. tools::codoc() run as part of R CMD check will complain if it doesn't.
• Not only make sure that examples are directly executable, also make sure that they are system-independent (do not use system) and do not require special facilities (for example Internet access or write permission to specific directories).
• Use quotation marks sparingly: quotation marks are used for R objects in text rendition. If you must use them, make them double (\dQuote{a quotation}), and use \sQuote and \dQuote
• Do not use tabs to indent (as these do not render correctly on all possible pagers).
• Please put two spaces after the end of a sentence in sections with running text (\description, \details, ...).
• For consistency, aim to use British (rather than American) spelling. (NB: British spelling often uses -ize as in 'capitalize'. The view of spell -b of British spelling is a flawed American one. There are English/Scottish differences too.)
• Do not use & except where quoting (for example, the publisher that has been called Chapman & Hall fairly recently).