

_D_o_c_u_m_e_n_t_a_t_i_o_n

     help(topic, offline = FALSE, package = c(.packages(), .Autoloaded),
          lib.loc = .lib.loc, verbose = .Options$verbose,
           htmlhelp = .Options$htmlhelp)
     ?topic

_A_r_g_u_m_e_n_t_s:

   topic: a name or character string on which documentation
          is sought (but not a variable containing a charac-
          ter string!).

 offline: a logical indicating whether documentation should
          be displayed on-line to the screen (the default)
          or hardcopy of it should be produced.

 package: a name or character vector giving the packages to
          look into for documentation.  By default, all
          packages in the search path are used.

 lib.loc: A character vector of directory names of R
          libraries.  Defaults to all libraries currently
          known.

 verbose: logical; if `TRUE', the file name is reported.

htmlhelp: logical (or `NULL').  If `TRUE' (which is the
          default after `help.start' has been called), the
          HTML version of the help will be shown in a
          browser.

_D_e_s_c_r_i_p_t_i_o_n:

     These functions provide access to documentation.  Docu-
     mentation on a topic with name `name' (typically, an R
     object or a data set) can be printed with either
     `help(name)' or `?name'.  In the case of unary and
     binary operators and control-flow special forms, the
     name may need to be be quoted.

     If `offline' is `TRUE', hardcopy of the documentation
     is produced by running the LaTeX version of the help
     page through `latex' (note that LaTeX 2e is needed) and
     `dvips'.  Depending on your `dvips' configuration,
     hardcopy will be sent to the printer or saved in a
     file.  If the programs are in non-standard locations
     and hence were not found at compile time, you can
     either set the options `latexcmd' and `dvipscmd', or
     the environment variables `R_LATEXCMD' and `R_DVIPSCMD'
     appropriately.  The appearance of the output can be
     customized through a file `Rhelp.cfg' somewhere in your
     LaTeX search path.

_N_o_t_e:

     The help files can be many small files. On some file
     systems it is desirable to save space, and the text
     files in the `help' directory of an installed package
     can be zipped up as a zip archive `Rhelp.zip'. Ensure
     the files `AnIndex' and `00Titles' remain un-zipped.
     Similarly, all the files in the `latex' directory can
     be zipped to `Rhelp.zip'.

_S_e_e _A_l_s_o:

     `help.start()' which opens the HTML version of the R
     Manual; `library()' for listing available packages and
     the user-level objects they contain; `data()' for list-
     ing available data sets; `methods()'.

     See `prompt()' to get a prototype for writing `help'
     pages of private packages.

_E_x_a_m_p_l_e_s:

     help()
     help(help)              # the same

     help(lapply)
     ?lapply                 # the same

     help("for")             # or ?"for", but the quotes are needed
     ?"+"

     help(package = stepfun) # get help even when it's not present

     data()                  # list all available data sets
     ?women                  # information about data set "women"

     topi <- "women"
     help(topi) ##--> Error: No documentation for `topi'

