R 3.0.1 (codename “Good Sport”) was released last week. As mentioned earlier by David, this version improves serialization performance with big objects, improves reliability for parallel programming and fixes a few minor bugs.

Upgrading to R 3.0.1

You can download the latest version from here. Or, if you are using windows, you can upgrade to the latest version using the installr package (also available on CRAN and github). Simply run the following code:

# installing/loading the package:
if(!require(installr)) { 
install.packages("installr"); require(installr)} #load / install+load installr
 
updateR(to_checkMD5sums = FALSE) # the use of to_checkMD5sums is because of a slight bug in the MD5 file on R 3.0.1. Soon this should get resolved and you could go back to using updateR(), install.R() or the menu upgrade system.

I try to keep the installr package updated and useful. If you have any suggestions or remarks on the package, you’re invited to leave a comment below.

If you use the global library system (as I do), you can run the following in the new version of R:

source("http://www.r-statistics.com/wp-content/uploads/2010/04/upgrading-R-on-windows.r.txt")
New.R.RunMe()

R 3.0.1 NEWS:

This is the relevant part of the NEWS file

CHANGES IN R 3.0.1:

  NEW FEATURES:

    o chooseCRANmirror() and chooseBioCmirror() gain an ind argument
      (like setRepositories()).

    o mcparallel has a new argument mc.interactive which can modify the
      interactive flag in the child process. The new default is FALSE
      which makes child processes non-interactive by default (this
      prevents lock-ups due to children waiting for interactive input).

    o scan() now warns when end-of-file occurs within a quoted string.

    o count.fields() is now consistent with scan() in its handling of
      newlines in quoted strings.  Instead of triggering an error, this
      results in the current line receiving NA as the field count, with
      the next line getting the total count of the two lines.

    o The default method of image() will plot axes of the class of xlim
      and ylim (and hence of x and y if there is a suitable range()
      method).  Based on a suggestion of Michael Sumner.

    o load() now has a verbose argument for debugging support, to print
      the names of objects just before loading them.

    o When loading a serialized object encounters a reference to a
      namespace which cannot be loaded, this is replaced by a reference
      to the global environment, with a warning.

    o pairs() gains a line.main option for title placement.

    o The remaining instances in which serialization to a raw vector
      was limited to 2GB have been unlimited on a 64-bit platform, and
      in most cases serialization to a vector of more than 1GB will be
      substantially faster.

  UTILITIES:

    o R CMD config now make use of personal Makevars files under ~/.R
      and a site file Makevars.site, in the same way as R CMD SHLIB and
      R CMD INSTALL.  This makes the utility more useful in package
      configure scripts.

      On Windows finding the personal files may require the environment
      variable HOME set.

      The old behaviour can be obtained with the new options
      --no-user-files and --no-site-files.

  PACKAGE INSTALLATION:

    o Alternatives to the site and user customization files
      Makevars.site and ~/.R/Makevars can be specified _via_ the
      environment variables R_MAKEVARS_SITE and R_MAKEVARS_USER
      respectively.  These can be used to suppress the use of the
      default files by setting an empty value (where possible) or a
      non-existent path.

  BUG FIXES:

    o sys.source() did not report error locations when keep.source =
      TRUE.

    o as.POSIXct.numeric was coercing origin using the tz argument and
      not "GMT" as documented (PR#14973).

    o The active binding to assign fields in reference classes has been
      cleaned up to reduce dependence on the class' package
      environment, also fixing bug in initializing read-only fields
      (inspired by a report from Hadley Wickham).

    o str(d) no longer gives an error when names(d) contain illegal
      multibyte strings (PR#15247).

    o Profiling of built-in functions with line.profiling= TRUE did not
      record the line from which they were called.

    o citation(pkg) dropped the header and footer specified in the
      CITATION file (PR#15257).

    o Quotes were handled differently when reading the first line and
      reading the rest, so read.table() misread some files that
      contained quote characters (PR#15245).

    o cat() with sep a character vector of length greater than one and
      more than one argument was using separators inconsistently
      (PR#15261).

    o On Windows in R 3.0.0, savePlot() failed because of an incorrect
      check on the argument count.

    o unzip(list = TRUE) returned Names as a factor and not a character
      vector (as documented) for the internal method.  (Noticed by Sean
      O'Riordain.)

    o contourLines() now checks more comprehensively for conformance of
      its x, y and z arguments (it was used incorrectly in package
      R2G2).

    o Saved graphics display lists are R version-specific.  Attempting
      to load workspaces containing them (or some other
      version-specific objects) aborted the load in R 3.0.0 and
      earlier; now it does a partial load and generates a warning
      instead.

    o In R 3.0.0, identify() and locator() did not record information
      correctly, so replaying a graph (e.g. by copying it to another
      device) would fail. (PR#15271)

    o Calling file.copy() or dirname() with the invalid input "" (which
      was being used in packages, despite not being a file path) could
      have caused a segfault.

      dirname("") is now "" rather than "." (unless it segfaulted).

    o supsmu() could read/write outside its input vectors for very
      short inputs (seen in package rms for n = 4).

    o as.dendrogram()'s hclust method uses less memory and hence gets
      considerably faster for large (n ~ 1000) clusterings, thanks to
      Daniel M"ullner. (PR#15174)

    o The return value when all workers failed from
      parallel::mclapply(mc.presechedule = TRUE) was a list of strings
      and not of error objects.  (Spotted by Karl Forner and Bernd
      Bischl.)

    o In R 3.0.0, when help() found multiple pages with the same alias,
      the HTML display of all the selections was not produced.
      (PR#15282)

    o splinefun(method="monoH.FC") now produces a function with first
      argument named x and allows deriv=3, as documented. (PR#15273)

    o summaryRprof() would only read the first chunksize lines of an
      Rprof file produced with line.profiling=TRUE. By default, this is
      the first 100 seconds.  (PR#15288)

    o lsfit() produced an incorrect error message when argument x had
      more columns than rows or x had a different number of rows than
      y. (Spotted by Renaud Gaujoux.)

    o Binary operations on equal length vectors copied the class name
      from the second operand when the first had no class name, but did
      not set the object bit. (PR#15299)

    o The trace() method for reference generator objects failed after
      those objects became function definitions.

    o write.table() did not check that factors were constructed
      correctly, and so caused a segment fault when writing bad ones.
      (PR#15300)

    o The internal HTTP server no longer chokes on POST requests
      without body. It will also pass-through other request types for
      custom handlers (with the method stored in Request-Method header)
      instead of failing.