[R-gregmisc-users] SF.net SVN: r-gregmisc:[1761] trunk/gtools

[<wa...@us...>]

Revision: 1761
          http://sourceforge.net/p/r-gregmisc/code/1761
Author:   warnes
Date:     2013-12-23 18:48:15 +0000 (Mon, 23 Dec 2013)
Log Message:
-----------
Extend the keywords() function to return keywords associated with a specified topic via 'keywords(topic)'.

Modified Paths:
--------------
    trunk/gtools/R/keywords.R
    trunk/gtools/man/keywords.Rd

Modified: trunk/gtools/R/keywords.R
===================================================================
--- trunk/gtools/R/keywords.R	2013-12-23 16:08:10 UTC (rev 1760)
+++ trunk/gtools/R/keywords.R	2013-12-23 18:48:15 UTC (rev 1761)
@@ -1,5 +1,33 @@
-keywords <- function( ... )
+keywords <- function( topic )
 {
+
   file <- file.path(R.home("doc"),"KEYWORDS")
-  file.show(file, ...)
+  if(missing(topic))
+      {
+          file.show(file)
+      }
+  else
+      {
+          kw <- scan(file=file, what=character(), sep="\n", quiet=TRUE)
+          kw <- grep("&", kw, value=TRUE)
+          kw <- gsub("&[^&]*$","", kw)
+          kw <- gsub("&+"," ", kw)
+          kw <- na.omit(trim(kw))
+
+          ischar <- tryCatch(is.character(topic) && length(topic) ==
+                             1L, error = identity)
+          if (inherits(ischar, "error"))
+              ischar <- FALSE
+          if (!ischar)
+              topic <- deparse(substitute(topic))
+
+          item <- paste("^",topic,"$", sep="")
+
+          topics <- function(k) help.search(keyword=k)$matches[,"topic"]
+          matches <- lapply(kw, topics)
+          names(matches) <- kw
+
+          tmp <- unlist(lapply( matches, function(m) grep(item, m, value=TRUE) ))
+          names(tmp)
+      }
 }

Modified: trunk/gtools/man/keywords.Rd
===================================================================
--- trunk/gtools/man/keywords.Rd	2013-12-23 16:08:10 UTC (rev 1760)
+++ trunk/gtools/man/keywords.Rd	2013-12-23 18:48:15 UTC (rev 1761)
@@ -5,21 +5,24 @@
   List valid keywords for R man pages
 }
 \usage{
-keywords(...)
+keywords(topic)
 }
 \arguments{
-  \item{\dots}{Optional argumenst to pass to show.file()}
+  \item{topic}{object or man page topic}
 }
 \details{
-  This function simply determines the path \$RHOME/doc/KEYWORDS and calls
-  show.file() to display it.
+  If \code{topic} is provided, return a list of the keywords associated
+  with \code{topic}.  Otherwise, display the list of valid R keywords
+  from the R doc/KEYWORDS file.
 }
-\value{
-  Nothing of interest.
-}
 \author{Gregory R. Warnes \email{gr...@wa...}}
 \seealso{ \code{\link[utils]{help}} }
 \examples{
+## Show all valid R keywords
 keywords()
+
+## Show keywords associated with the 'merge' function
+keywords(merge)
+keywords("merge")
 }
 \keyword{documentation}

This was sent by the SourceForge.net collaborative development platform, the world's largest Open Source development site.