R News

CHANGES IN R 3.0.2:

  NEW FEATURES:

    • The NEWS files have been re-organized.

      This file contains news for R >= 3.0.0: news for the 0.x.y, 1.x.y
      and 2.x.y releases is in files NEWS.0, NEWS.1 and NEWS.2.  The
      latter files are now installed when R is installed.  An HTML
      version of news from 2.10.0 to 2.15.3 is available as
      doc/html/NEWS.2.html.

    • sum() for integer arguments now uses an integer accumulator of at
      least 64 bits and so will be more accurate in the very rare case
      that a cumulative sum exceeds 2^53 (necessarily summing more than
      4 million elements).

    • The example() and tools::Rd2ex() functions now have parameters to
      allow them to ignore \dontrun markup in examples.  (Suggested by
      Peter Solymos.)

    • str(x) is considerably faster for very large lists, or factors
      with 100,000 levels, the latter as in PR#15337.

    • col2rgb() now converts factors to character strings not integer
      codes (suggested by Bryan Hanson).

    • tail(warnings()) now works, via the new `[` method.

    • There is now support for the LaTeX style file zi4.sty which has
      in some distributions replaced inconsolata.sty.

    • unlist(x) now typically returns all non-list xs unchanged, not
      just the “vector” ones.  Consequently, format(lst) now also works
      when the list lst has non-vector elements.

    • The tools::getVignetteInfo() function has been added to give
      information about installed vignettes.

    • New assertCondition(), etc. utilities in tools, useful for
      testing.

    • Profiling now records non-inlined calls from byte-compiled code
      to BUILTIN functions.

    • Various functions in stats and elsewhere that use non-standard
      evaluation are now more careful to follow the namespace scoping
      rules.  E.g. stats::lm() can now find stats::model.frame() even
      if stats is not on the search path or if some package defines a
      function of that name.

    • If an invalid/corrupt .Random.seed object is encountered in the
      workspace it is ignored with a warning rather than giving an
      error.  (This allows R itself to rely on a working RNG, e.g. to
      choose a random port.)

    • seq() and seq.int() give more explicit error messages if called
      with invalid (e.g. NaN) inputs.

    • When parse() finds a syntax error, it now makes partial parse
      information available up to the location of the error.  (Request
      of Reijo Sund.)

    • Methods invoked by NextMethod() had a different dynamic parent to
      the generic. This was causing trouble where S3 methods invoked
      via lazy evaluation could lose track of their generic.
      (PR#15267)

    • Code for the negative binomial distribution now treats the case
      size == 0 as a one-point distribution at zero.

    • abbreviate() handles without warning non-ASCII input strings
      which require no abbreviation.

    • read.dcf() no longer has a limit of 8191 bytes per line. (Wish of
      PR#15250.)

    • formatC(x) no longer copies the class of x to the result, to
      avoid misuse creating invalid objects as in PR#15303.  A warning
      is given if a class is discarded.

    • Dataset npk has been copied from MASS to allow more tests to be
      run without recommended packages being installed.

    • The initialization of the regression coefficients for
      non-degenerate differenced models in arima() has been changed and
      in some examples avoids a local maximum.  (PR#15396)

    • termplot() now has an argument transform.x to control the display
      of individual terms in the plot.  (PR#15329)

    • format() now supports digits = 0, to display nsmall decimal
      places.

    • There is a new read-only par() parameter called "page", which
      returns a logical value indicating whether the next plot.new()
      call will start a new page.

    • Processing Sweave and Rd documents to PDF now renders backticks
      and single quotes better in several instances, including in \code
      and \samp expressions.

    • utils::modifyList() gets a new argument keep.null allowing NULL
      components in the replacement to be retained, instead of causing
      corresponding components to be deleted.

    • tools::pkgVignettes() gains argument check; if set to TRUE, it
      will warn when it appears a vignette requests a non-existent
      vignette engine.

  UTILITIES:

    • R CMD check --as-cran checks the line widths in usage and
      examples sections of the package Rd files.

    • R CMD check --as-cran now implies --timings.

    • R CMD check looks for command gfile if a suitable file is not
      found.  (Although file is not from GNU, OpenCSW on Solaris
      installs it as gfile.)

    • R CMD build (with the internal tar) checks the permissions of
      configure and cleanup files and adds execute permission to the
      recorded permissions for these files if needed, with a warning.
      This is useful on OSes and file systems which do not support
      execute permissions (notably, on Windows).

    • R CMD build now weaves and tangles all vignettes, so suggested
      packages are not required during package installation if the
      source tarball was prepared with current R CMD build.

    • checkFF() (used by R CMD check) does a better job of detecting
      calls from other packages, including not reporting those where a
      function has been copied from another namespace (e.g. as a
      default method).  It now reports calls where .NAME is a symbol
      registered in another package.

    • On Unix-alike systems, R CMD INSTALL now installs packages group
      writably whenever the library (lib.loc) is group writable.
      Hence, update.packages() works for other group members (suggested
      originally and from a patch by Dirk Eddelbuettel).

    • R CMD javareconf now supports the use of symbolic links for
      JAVA_HOME on platforms which have realpath.  So it is now
      possible to use
      
      R CMD javareconf JAVA_HOME=/usr/lib/jvm/java-1.7.0

      on a Linux system and record that value rather than the
      frequently-changing full path such as
      /usr/lib/jvm/java-1.7.0-openjdk-1.7.0.25.x86_64.

    • (Windows only.) Rscript -e requires a non-empty argument for
      consistency with Unix versions of R.  (Also Rterm -e and R -e.)

    • R CMD check does more thorough checking of declared packages and
      namespaces.  It reports

        • packages declared in more than one of the Depends, Imports,
          Suggests and Enhances fields of the DESCRIPTION file.

        • namespaces declared in Imports but not imported from, neither
          in the NAMESPACE file nor using the :: nor ::: operators.

        • packages which are used in library() or requires() calls in
          the R code but were already put on the search path _via_
          Depends.

        • packages declared in Depends not imported _via_ the NAMESPACE
          file (except the standard packages).  Objects used from
          Depends packages should be imported to avoid conflicts and to
          allow correct operation when the namespace is loaded but not
          attached.

        • objects imported _via_ ::: calls where :: would do.

        • objects imported by :: which are not exported.

        • objects imported by ::: calls which do not exist.

      See ‘Writing R Extensions’ for good practice.

    • R CMD check optionally checks for non-standard top-level files
      and directories (which are often mistakes): this is enabled for
      --as-cran.

    • LaTeX style file upquote.sty is no longer included (the version
      was several years old): it is no longer used in R.  A much later
      version is commonly included in LaTeX distributions but does not
      play well with the ae fonts which are the default for Sweave
      vignettes.

    • R CMD build makes more use of the build sub-directory of package
      sources, for example to record information about the vignettes.

  INSTALLATION and INCLUDED SOFTWARE:

    • The macros used for the texinfo manuals have been changed to work
      better with the incompatible changes made in texinfo 5.x.

    • The minimum version for a system xz library is now 5.0.3 (was
      4.999).  This is in part to avoid 5.0.2, which can compress in
      ways other versions cannot decompress.

    • The included version of PCRE has been updated to 8.33.

    • The included version of zlib has been updated to 1.2.8, a bug-fix
      release.

    • The included version of xz utils's liblzma has been updated to
      5.0.5.

    • Since javareconf (see above) is used when R is installed, a
      stable link for JAVA_HOME can be supplied then.

    • Configuring with --disable-byte-compilation will override the
      DESCRIPTION files of recommended packages, which typically
      require byte-compilation.

    • More of the installation and checking process will work even when
      TMPDIR is set to a path containing spaces, but this is not
      recommended and external software (such as texi2dvi) may fail.

  PACKAGE INSTALLATION:

    • Installation is aborted immediately if a LinkingTo package is not
      installed.

    • R CMD INSTALL has a new option --no-byte-compile which will
      override a ByteCompile field in the package's DESCRIPTION file.

    • License BSD is deprecated: use BSD_3_clause or BSD_2_clause
      instead.

      License X11 is deprecated: use MIT or BSD_2_clause instead.

    • Version requirements for LinkingTo packages are now recognized:
      they are checked at installation.  (Fields with version
      requirements were previously silently ignored.)

    • The limit of 500 S3method entries in a NAMESPACE file has been
      removed.

    • The default ‘version’ of Bioconductor for its packages has been
      changed to the upcoming 2.13, but this can be set by the
      environment variable R_BIOC_VERSION, e.g.  in file Renviron.site.

  C-LEVEL FACILITIES:

    • Rdefines.h has been tweaked so it can be included in C++ code
      after R_ext/Boolean.h (which is included by R.h).

      Note that Rdefines.h is not kept up-to-date, and Rinternals.h is
      preferred for new code.

    • eval and applyClosure are now protected against package code
      supplying an invalid rho.

  DEPRECATED AND DEFUNCT:

    • The unused namespace argument to package.skeleton() is now
      formally deprecated and will be removed in R 3.1.0.

    • plclust() is deprecated: use the plot() method for class "hclust"
      instead.

    • Functions readNEWS() and checkNEWS() in package tools are
      deprecated (and they have not worked with current NEWS files for
      a long time).

  DOCUMENTATION:

    • ‘An Introduction to R’ has a new chapter on using R as a
      scripting language including interacting with the OS.

  BUG FIXES:

    • help.request() could not determine the current version of R on
      CRAN.  (PR#15241)

    • On Windows, file.info() failed on root directories unless the
      path was terminated with an explicit ".".  (PR#15302)

    • The regmatches<-() replacement function mishandled results coming
      from regexpr().  (PR#15311)

    • The help for setClass() and representation() still suggested the
      deprecated argument representation=. (PR#15312)

    • R CMD config failed in an installed build of R 3.0.1 (only) when
      a sub-architecture was used.  (Reported by Berwin Turlach.)

    • On Windows, the installer modified the etc/Rconsole and
      etc/Rprofile.site files even when default options were chosen, so
      the MD5 sums did not refer to the installed versions.  (Reported
      by Tal Galili.)

    • plot(hclust(), cex =) respects cex again (and possibly others
      similarly).  (Reported by Peter Langfelder.)

    • If multiple packages were checked by R CMD check, and one was
      written for a different OS, it would set --no-install for all
      following packages as well as itself.

    • qr.coef() and related functions did not properly coerce real
      vectors to complex when necessary.  (PR#15332)

    • ftable(a) now fixes up empty dimnames such that the result is
      printable.

    • package.skeleton() was not starting its search for function
      objects in the correct place if environment was supplied.
      (Reported by Karl Forner.)

    • Parsing code was changing the length field of vectors and
      confusing the memory manager.  (PR#15345)

    • The Fortran routine ZHER2K in the reference BLAS had a
      comment-out bug in two places.  This caused trouble with eigen()
      for Hermitian matrices.  (PR#15345 and report from Robin Hankin)

    • vignette() and browseVignettes() did not display non-Sweave
      vignettes properly.

    • Two warning/error messages have been corrected: the (optional)
      warning produced by a partial name match with a pairlist, the
      error message from a zero-length argument to the : operator.
      (Found by Radford Neal; PR#15358, PR#15356)

    • svd() returned NULL rather than omitting components as
      documented.  (Found by Radford Neal; PR#15360)

    • mclapply() and mcparallel() with silent = TRUE could break a
      process that uses stdout output unguarded against broken pipes
      (e.g., zip will fail silently). To work around such issues, they
      now replace stdout with a descriptor pointed to /dev/null
      instead. For this purpose, internal closeStdout and closeStderr
      functions have gained the to.null flag.

    • log(), signif() and round() now raise an error if a single named
      argument is not named x.  (PR#15361)

    • deparse() now deparses raw vectors in a form that is
      syntactically correct. (PR#15369)

    • The jpeg driver in Sweave created a JPEG file, but gave it a .png
      extension. (PR#15370)

    • Deparsing of infix operators with named arguments is improved.
      (PR#15350)

    • mget(), seq.int() and numericDeriv() did not duplicate arguments
      properly. (PR#15352, PR#15353, PR#15354)

    • kmeans(algorithm = "Hartigan-Wong") now always stops iterating in
      the QTran stage. (PR#15364).

    • read.dcf() re-allocated incorrectly and so could segfault when
      called on a file with lines of more than 100 bytes.

    • On systems where mktime() does not set errno, the last second
      before the epoch could not be converted from POSIXlt to POSIXct.
      (Reported by Bill Dunlap.)

    • add1.glm() miscalculated F-statistics when df > 1. (Bill Dunlap,
      PR#15386).

    • stem() now discards infinite inputs rather than hanging.
      (PR#15376)

    • The parser now enforces C99 syntax for floating point hexadecimal
      constants (e.g. 0x1.1p0), rather than returning unintended values
      for malformed constants. (PR#15234)

    • model.matrix() now works with very long LHS names (more than 500
      bytes).  (PR#15377)

    • integrate() reverts to the pre-2.12.0 behaviour: from 2.12.0 to
      3.0.1 it sometimes failed to achieve the requested tolerance and
      reported error estimates that were exceeded.  (PR#15219)

    • strptime() now handles %W fields with value 0. (PR#15915)

    • R is now better protected against people trying to interact with
      the console in startup code.  (PR#15325)

    • Subsetting 1D arrays often lost dimnames (PR#15301).

    • Unary + on a logical vector did not coerce to integer, although
      unary - did.

    • na.omit() and na.exclude() added a row to a zero-row data frame.
      (PR#15399)

    • All the (where necessary cut-down) vignettes are installed if R
      was configured with --without-recommended-packages.

    • source() did not display filenames when reporting syntax errors.

    • Syntax error reports misplaced the caret pointing out the bad
      token.

    • (Windows only) Starting R with R (instead of Rterm or Rgui) would
      lose any zero-length strings from the command line arguments.
      (PR#15406)

    • Errors in the encoding specified on the command line via
      --encoding=foo were not handled properly.  (PR#15405)

    • If x is a symbol, is.vector(x, "name") now returns TRUE, since
      "name" and "symbol" should be synonyms.  (Reported by Hervé
      Pagès.)

    • R CMD rtags works on platforms (such as OS X) with a
      XSI-conformant shell command echo. (PR#15231)

    • is.unsorted(NA) returns false as documented (rather than NA).

    • R CMD LINK did not know about sub-architectures.

    • system() and system2() are better protected against users who
      misguidedly have spaces in the temporary directory path.

    • file.show() and edit() are now more likely to work on file paths
      containing spaces.  (Where external utilities are used, not the
      norm on Windows nor in R.app which should previously have
      worked.)

    • Packages using the methods package are more likely to work when
      they import it but it is not attached.  (Several parts of its C
      code were looking for its R functions on the search path rather
      than in its namespace.)

    • lgamma(-x) is no longer NaN for very small x.

    • (Windows) system2() now respects specifying stdout and stderr as
      files if called from Rgui. (PR#15393)

    • Closing an x11() device whilst locator() or identify() is in
      progress no longer hangs R.  (PR#15253)

    • list.dirs(full.names = FALSE) was not implemented.  (PR#15170)

    • format() sometimes added unnecessary spaces.  (PR#15411)

    • all.equal(check.names = FALSE) would ignore the request to ignore
      the names and would check them as attributes.

    • The symbol set by tools::Rd2txt_options(itemBullet=) was not
      respected in some locales. (PR#15435)

    • mcMap() was not exported by package parallel. (PR#15439)

    • plot() for TukeyHSD objects did not balance dev.hold() and
      dev.flush() calls on multi-page plots.  (PR#15449)

CHANGES IN R 3.0.1:

  NEW FEATURES:

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

    • 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).

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

    • 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.

    • 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.

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

    • 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.

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

    • 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:

    • 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:

    • 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:

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

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

    • 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).

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

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

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

    • 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).

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

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

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

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

    • 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.

    • 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)

    • 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).

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

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

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

    • 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)

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

    • 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)

    • 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.)

    • 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)

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

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

    • 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.

CHANGES IN R 3.0.0:

  SIGNIFICANT USER-VISIBLE CHANGES:

    • Packages need to be (re-)installed under this version (3.0.0) of
      R.

    • There is a subtle change in behaviour for numeric index values
      2^31 and larger.  These never used to be legitimate and so were
      treated as NA, sometimes with a warning.  They are now legal for
      long vectors so there is no longer a warning, and x[2^31] <- y
      will now extend the vector on a 64-bit platform and give an error
      on a 32-bit one.

    • It is now possible for 64-bit builds to allocate amounts of
      memory limited only by the OS.  It may be wise to use OS
      facilities (e.g. ulimit in a bash shell, limit in csh), to set
      limits on overall memory consumption of an R process,
      particularly in a multi-user environment.  A number of packages
      need a limit of at least 4GB of virtual memory to load.

      64-bit Windows builds of R are by default limited in memory usage
      to the amount of RAM installed: this limit can be changed by
      command-line option --max-mem-size or setting environment
      variable R_MAX_MEM_SIZE.

    • Negative numbers for colours are consistently an error:
      previously they were sometimes taken as transparent, sometimes
      mapped into the current palette and sometimes an error.

  NEW FEATURES:

    • identical() has a new argument, ignore.environment, used when
      comparing functions (with default FALSE as before).

    • There is a new option, options(CBoundsCheck=), which controls how
      .C() and .Fortran() pass arguments to compiled code.  If true
      (which can be enabled by setting the environment variable
      R_C_BOUNDS_CHECK to yes), raw, integer, double and complex
      arguments are always copied, and checked for writing off either
      end of the array on return from the compiled code (when a second
      copy is made).  This also checks individual elements of character
      vectors passed to .C().

      This is not intended for routine use, but can be very helpful in
      finding segfaults in package code.

    • In layout(), the limits on the grid size have been raised
      (again).

    • New simple provideDimnames() utility function.

    • Where methods for length() return a double value which is
      representable as an integer (as often happens for package
      Matrix), this is converted to an integer.

    • Matrix indexing of dataframes by two-column numeric indices is
      now supported for replacement as well as extraction.

    • setNames() now has a default for its object argument, useful for
      a character result.

    • StructTS() has a revised additive constant in the loglik
      component of the result: the previous definition is returned as
      the loglik0 component.  However, the help page has always warned
      of a lack of comparability of log-likelihoods for non-stationary
      models.  (Suggested by Jouni Helske.)

    • The logic in aggregate.formula() has been revised.  It is now
      possible to use a formula stored in a variable; previously, it
      had to be given explicitly in the function call.

    • install.packages() has a new argument quiet to reduce the amount
      of output shown.

    • Setting an element of the graphics argument lwd to a negative or
      infinite value is now an error.  Lines corresponding to elements
      with values NA or NaN are silently omitted.

      Previously the behaviour was device-dependent.

    • Setting graphical parameters cex, col, lty, lwd and pch in par()
      now requires a length-one argument.  Previously some silently
      took the first element of a longer vector, but not always when
      documented to do so.

    • Sys.which() when used with inputs which would be unsafe in a
      shell (e.g. absolute paths containing spaces) now uses
      appropriate quoting.

    • as.tclObj() has been extended to handle raw vectors.  Previously,
      it only worked in the other direction.  (Contributed by Charlie
      Friedemann, PR#14939.)

    • New functions cite() and citeNatbib() have been added, to allow
      generation of in-text citations from "bibentry" objects.  A
      cite() function may be added to bibstyle() environments.

    • A sort() method has been added for "bibentry" objects.

    • The bibstyle() function now defaults to setting the default
      bibliography style. The getBibstyle() function has been added to
      report the name of the current default style.

    • scatter.smooth() now has an argument lpars to pass arguments to
      lines().

    • pairs() has a new log argument, to allow some or all variables to
      be plotted on logarithmic scale.  (In part, wish of PR#14919.)

    • split() gains a sep argument.

    • termplot() does a better job when given a model with interactions
      (and no longer attempts to plot interaction terms).

    • The parser now incorporates code from Romain Francois' parser
      package, to support more detailed computation on the code, such
      as syntax highlighting, comment-based documentation, etc.
      Functions getParseData() and getParseText() access the data.

    • There is a new function rep_len() analogous to rep.int() for when
      speed is required (and names are not).

    • The undocumented use rep(NULL, length.out = n) for n > 0 (which
      returns NULL) now gives a warning.

    • demo() gains an encoding argument for those packages with
      non-ASCII demos: it defaults to the package encoding where there
      is one.

    • strwrap() converts inputs with a marked encoding to the current
      locale: previously it made some attempt to pass through as bytes
      inputs invalid in the current locale.

    • Specifying both rate and scale to [dpqr]gamma is a warning (if
      they are essentially the same value) or an error.

    • merge() works in more cases where the data frames include
      matrices.  (Wish of PR#14974.)

    • optimize() and uniroot() no longer use a shared parameter object
      across calls.  (nlm(), nlminb() and optim() with numerical
      derivatives still do, as documented.)

    • The all.equal() method for date-times is now documented: times
      are regarded as equal (by default) if they differ by up to 1
      msec.

    • duplicated() and unique() gain a nmax argument which can be used
      to make them much more efficient when it is known that there are
      only a small number of unique entries.  This is done
      automatically for factors.

    • Functions rbinom(), rgeom(), rhyper(), rpois(), rnbinom(),
      rsignrank() and rwilcox() now return integer (not double)
      vectors.  This halves the storage requirements for large
      simulations.

    • sort(), sort.int() and sort.list() now use radix sorting for
      factors of less than 100,000 levels when method is not supplied.
      So does order() if called with a single factor, unless na.last =
      NA.

    • diag() as used to generate a diagonal matrix has been re-written
      in C for speed and less memory usage.  It now forces the result
      to be numeric in the case diag(x) since it is said to have ‘zero
      off-diagonal entries’.

    • backsolve() (and forwardsolve()) are now internal functions, for
      speed and support for large matrices.

    • More matrix algebra functions (e.g. chol() and solve()) accept
      logical matrices (and coerce to numeric).

    • sample.int() has some support for n >= 2^31: see its help for the
      limitations.

      A different algorithm is used for (n, size, replace = FALSE, prob
      = NULL) for n > 1e7 and size <= n/2.  This is much faster and
      uses less memory, but does give different results.

    • approxfun() and splinefun() now return a wrapper to an internal
      function in the stats namespace rather than a .C() or .Call()
      call.  This is more likely to work if the function is saved and
      used in a different session.

    • The functions .C(), .Call(), .External() and .Fortran() now give
      an error (rather than a warning) if called with a named first
      argument.

    • Sweave() by default now reports the locations in the source
      file(s) of each chunk.

    • clearPushBack() is now a documented interface to a long-existing
      internal call.

    • aspell() gains filters for R code, Debian Control Format and
      message catalog files, and support for R level dictionaries.  In
      addition, package utils now provides functions
      aspell_package_R_files() and aspell_package_C_files() for spell
      checking R and C level message strings in packages.

    • bibentry() gains some support for “incomplete” entries with a
      crossref field.

    • gray() and gray.colors() finally allow alpha to be specified.

    • monthplot() gains parameters to control the look of the reference
      lines.  (Suggestion of Ian McLeod.)

    • Added support for new %~% relation (“is distributed as”) in
      plotmath.

    • domain = NA is accepted by gettext() and ngettext(), analogously
      to stop() etc.

    • termplot() gains a new argument plot = FALSE which returns
      information to allow the plots to be modified for use as part of
      other plots, but does not plot them.  (Contributed by Terry
      Therneau, PR#15076.)

    • quartz.save(), formerly an undocumented part of R.app, is now
      available to copy a device to a quartz() device.  dev.copy2pdf()
      optionally does this for PDF output: quartz.save() defaults to
      PNG.

    • The default method of pairs() now allows text.panel = NULL and
      the use of <foo>.panel = NULL is now documented.

    • setRefClass() and getRefClass() now return class generator
      functions, similar to setClass(), but still with the reference
      fields and methods as before (suggestion of Romain Francois).

    • New functions bitwNot(), bitwAnd(), bitwOr() and bitwXor(), using
      the internal interfaces previously used for classes "octmode" and
      "hexmode".

      Also bitwShiftL() and bitwShiftR() for shifting bits in elements
      of integer vectors.

    • New option "deparse.cutoff" to control the deparsing of language
      objects such as calls and formulae when printing.  (Suggested by
      a comment of Sarah Goslee.)

    • colors() gains an argument distinct.

    • New demo(colors) and demo(hclColors), with utility functions.

    • list.files() (aka dir()) gains a new optional argument no.. which
      allows to exclude "." and ".." from listings.

    • Multiple time series are also of class "matrix"; consequently,
      head(), e.g., is more useful.

    • encodeString() preserves UTF-8 marked encodings.  Thus if factor
      levels are marked as UTF-8 an attempt is made to print them in
      UTF-8 in RGui on Windows.

    • readLines() and scan() (and hence read.table()) in a UTF-8 locale
      now discard a UTF-8 byte-order-mark (BOM).  Such BOMs are allowed
      but not recommended by the Unicode Standard: however Microsoft
      applications can produce them and so they are sometimes found on
      websites.

      The encoding name "UTF-8-BOM" for a connection will ensure that a
      UTF-8 BOM is discarded.

    • mapply(FUN, a1, ..) now also works when a1 (or a further such
      argument) needs a length() method (which the documented arguments
      never do).  (Requested by Hervé Pagès; with a patch.)

    • .onDetach() is supported as an alternative to .Last.lib.  Unlike
      .Last.lib, this does not need to be exported from the package's
      namespace.

    • The srcfile argument to parse() may now be a character string, to
      be used in error messages.

    • The format() method for ftable objects gains a method argument,
      propagated to write.ftable() and print(), allowing more compact
      output, notably for LaTeX formatting, thanks to Marius Hofert.

    • The utils::process.events() function has been added to trigger
      immediate event handling.

    • Sys.which() now returns NA (not "") for NA inputs (related to
      PR#15147).

    • The print() method for class "htest" gives fewer trailing spaces
      (wish of PR#15124).

      Also print output from HoltWinters(), nls() and others.

    • loadNamespace() allows a version specification to be given, and
      this is used to check version specifications given in the Imports
      field when a namespace is loaded.

    • setClass() has a new argument, slots, clearer and less ambiguous
      than representation.  It is recommended for future code, but
      should be back-compatible.  At the same time, the allowed slot
      specification is slightly more general.  See the documentation
      for details.

    • mget() now has a default for envir (the frame from which it is
      called), for consistency with get() and assign().

    • close() now returns an integer status where available, invisibly.
      (Wish of PR#15088.)

    • The internal method of tar() can now store paths too long for the
      ustar format, using the (widely supported) GNU extension.  It can
      also store long link names, but these are much less widely
      supported.  There is support for larger files, up to the ustar
      limit of 8GB.

    • Local reference classes have been added to package methods.
      These are a technique for avoiding unneeded copying of large
      components of objects while retaining standard R functional
      behavior.  See ?LocalReferenceClasses.

    • untar() has a new argument restore_times which if false (not the
      default) discards the times in the tarball.  This is useful if
      they are incorrect (some tarballs submitted to CRAN have times in
      a local timezone or many years in the past even though the
      standard required them to be in UTC).

    • replayplot() cannot (and will not attempt to) replay plots
      recorded under R < 3.0.0.  It may crash the R session if an
      attempt is made to replay plots created in a different build of R
      >= 3.0.0.

    • Palette changes get recorded on the display list, so replaying
      plots (including when resizing screen devices and using
      dev.copy()) will work better when the palette is changed during a
      plot.

    • chol(pivot = TRUE) now defaults to LAPACK, not LINPACK.

    • The parse() function has a new parameter keep.source, which
      defaults to options("keep.source").

    • Profiling via Rprof() now optionally records information at the
      statement level, not just the function level.

    • The Rprof() function now quotes function names in in its output
      file on Windows, to be consistent with the quoting in Unix.

    • Profiling via Rprof() now optionally records information about
      time spent in GC.

    • The HTML help page for a package now displays non-vignette
      documentation files in a more accessible format.

    • To support options(stringsAsFactors = FALSE), model.frame(),
      model.matrix() and replications() now automatically convert
      character vectors to factors without a warning.

    • The print method for objects of class "table" now detects tables
      with 0-extents and prints the results as, e.g., < table of extent
      0 x 1 x 2 >. (Wish of PR#15198.)

    • Deparsing involving calls to anonymous functions has been made
      closer to reversible by the addition of extra parentheses.

    • The function utils::packageName() has been added as a lightweight
      version of methods::getPackageName().

    • find.package(lib.loc = NULL) now treats loaded namespaces
      preferentially in the same way as attached packages have been for
      a long time.

    • In Windows, the Change Directory dialog now defaults to the
      current working directory, rather than to the last directory
      chosen in that dialog.

    • available.packages() gains a "license/restricts_use" filter which
      retains only packages for which installation can proceed solely
      based on packages which are guaranteed not to restrict use.

    • New check_packages_in_dir() function in package tools for
      conveniently checking source packages along with their reverse
      dependencies.

    • R's completion mechanism has been improved to handle help
      requests (starting with a question mark).  In particular, help
      prefixes are now supported, as well as quoted help topics.  To
      support this, completion inside quotes are now handled by R by
      default on all platforms.

    • The memory manager now allows the strategy used to balance
      garbage collection and memory growth to be controlled by setting
      the environment variable R_GC_MEM_GROW. See ?Memory for more
      details.

    • (‘For experts only’, as the introductory manual says.)  The use
      of environment variables R_NSIZE and R_VSIZE to control the
      initial (= minimum) garbage collection trigger for number of cons
      cels and size of heap has been restored: they can be overridden
      by the command-line options --min-nsize and --min-vsize; see
      ?Memory.

    • On Windows, the device name for bitmap devices as reported by
      .Device and .Devices no longer includes the file name.  This is
      for consistency with other platforms and was requested by the
      lattice maintainer.

      win.metafile() still uses the file name: the exact form is used
      by package tkrplot.

    • set.seed(NULL) re-initializes .Random.seed as done at the
      beginning of the session if not already set.  (Suggestion of Bill
      Dunlap.)

    • The breaks argument in hist.default() can now be a function that
      returns the breakpoints to be used (previously it could only
      return the suggested number of breakpoints).

    • File share/licenses/licenses.db has some clarifications,
      especially as to which variants of ‘BSD’ and ‘MIT’ is intended
      and how to apply them to packages.  The problematic licence
      ‘Artistic-1.0’ has been removed.

  LONG VECTORS:

  This section applies only to 64-bit platforms.

    • There is support for vectors longer than 2^31 - 1 elements.  This
      applies to raw, logical, integer, double, complex and character
      vectors, as well as lists.  (Elements of character vectors remain
      limited to 2^31 - 1 bytes.)

    • Most operations which can sensibly be done with long vectors
      work: others may return the error ‘long vectors not supported
      yet’.  Most of these are because they explicitly work with
      integer indices (e.g. anyDuplicated() and match()) or because
      other limits (e.g. of character strings or matrix dimensions)
      would be exceeded or the operations would be extremely slow.

    • length() returns a double for long vectors, and lengths can be
      set to 2^31 or more by the replacement function with a double
      value.

    • Most aspects of indexing are available.  Generally double-valued
      indices can be used to access elements beyond 2^31 - 1.

    • There is some support for matrices and arrays with each dimension
      less than 2^31 but total number of elements more than that.  Only
      some aspects of matrix algebra work for such matrices, often
      taking a very long time.  In other cases the underlying Fortran
      code has an unstated restriction (as was found for complex
      svd()).

    • dist() can produce dissimilarity objects for more than 65536 rows
      (but for example hclust() cannot process such objects).

    • serialize() to a raw vector is unlimited in size (except by
      resources).

    • The C-level function R_alloc can now allocate 2^35 or more bytes.

    • agrep() and grep() will return double vectors of indices for long
      vector inputs.

    • Many calls to .C() have been replaced by .Call() to allow long
      vectors to be supported (now or in the future).  Regrettably
      several packages had copied the non-API .C() calls and so failed.

    • .C() and .Fortran() do not accept long vector inputs.  This is a
      precaution as it is very unlikely that existing code will have
      been written to handle long vectors (and the R wrappers often
      assume that length(x) is an integer).

    • Most of the methods for sort() work for long vectors.

      rank(), sort.list() and order() support long vectors (slowly
      except for radix sorting).

    • sample() can do uniform sampling from a long vector.

  PERFORMANCE IMPROVEMENTS:

    • More use has been made of R objects representing registered entry
      points, which is more efficient as the address is provided by the
      loader once only when the package is loaded.

      This has been done for packages base, methods, splines and tcltk:
      it was already in place for the other standard packages.

      Since these entry points are always accessed by the R entry
      points they do not need to be in the load table which can be
      substantially smaller and hence searched faster.  This does mean
      that .C / .Fortran / .Call calls copied from earlier versions of
      R may no longer work - but they were never part of the API.

    • Many .Call() calls in package base have been migrated to
      .Internal() calls.

    • solve() makes fewer copies, especially when b is a vector rather
      than a matrix.

    • eigen() makes fewer copies if the input has dimnames.

    • Most of the linear algebra functions make fewer copies when the
      input(s) are not double (e.g. integer or logical).

    • A foreign function call (.C() etc) in a package without a PACKAGE
      argument will only look in the first DLL specified in the
      NAMESPACE file of the package rather than searching all loaded
      DLLs.  A few packages needed PACKAGE arguments added.

    • The @<- operator is now implemented as a primitive, which should
      reduce some copying of objects when used.  Note that the operator
      object must now be in package base: do not try to import it
      explicitly from package methods.

  PACKAGE INSTALLATION:

    • The transitional support for installing packages without
      namespaces (required since R 2.14.0) has been removed.  R CMD
      build will still add a namespace, but a .First.lib() function
      will need to be converted.

      R CMD INSTALL no longer adds a namespace (so installation will
      fail), and a .First.lib() function in a package will be ignored
      (with an installation warning for now).

      As an exception, packages without a R directory and no NAMESPACE
      file can still be installed.

    • Packages can specify in their DESCRIPTION file a line like
      
           Biarch: yes

      to be installed on Windows with --force-biarch.

    • Package vignettes can now be processed by other engines besides
      Sweave; see ‘Writing R Extensions’ and the tools::vignetteEngine
      help topic for details.

    • The *.R tangled source code for vignettes is now included in
      tarballs when R CMD build is used to produce them.  In R 3.0.0,
      *.R files not in the sources will be produced at install time,
      but eventually this will be dropped.

    • The package type "mac.binary" now looks in a path in the
      repository without any Mac subtype (which used to be universal or
      leopard): it looks in bin/macosx/contrib/3.0 rather than
      bin/macosx/leopard/contrib/2.15).  This is the type used for the
      CRAN binary distribution for OS X as from R 3.0.0.

    • File etc/Makeconf makes more use of the macros $(CC), $(CXX),
      $(F77) and $(FC), so the compiler in use can be changed by
      setting just these (and if necessary the corresponding flags and
      FLIBS) in file ~/.R/Makevars.

      This is convenient for those working with binary distributions of
      R, e.g. on OS X.

  UTILITIES:

    • R CMD check now gives a warning rather than a note if it finds
      calls to abort, assert or exit in compiled code, and has been
      able to find the .o file in which the calls occur.

      Such calls can terminate the R process which loads the package.

    • The location of the build and check environment files can now be
      specified by the environment variables R_BUILD_ENVIRON and
      R_CHECK_ENVIRON, respectively.

    • R CMD Sweave gains a --compact option to control possibly
      reducing the size of the PDF file it creates when --pdf is given.

    • R CMD build now omits Eclipse's .metadata directories, and R CMD
      check warns if it finds them.

    • R CMD check now does some checks on functions defined within
      reference classes, including of .Call() etc calls.

    • R CMD check --as-cran notes assignments to the global
      environment, calls to data() which load into the global
      environment, and calls to attach().

    • R CMD build by default uses the internal method of tar() to
      prepare the tarball.  This is more likely to produce a tarball
      compatible with R CMD INSTALL and R CMD check: an external tar
      program, including options, can be specified _via_ the
      environment variable R_BUILD_TAR.

    • tools::massageExamples() is better protected against packages
      which re-define base functions such as cat() and get() and so can
      cause R CMD check to fail when checking examples.

    • R CMD javareconf has been enhanced to be more similar to the code
      used by configure.

      There is now a test that a JNI program can be compiled (like
      configure did) and only working settings are used.

      It makes use of custom settings from configuration recorded in
      etc/javaconf.

    • The --no-vignettes argument of R CMD build has been renamed to
      the more accurate --no-build-vignettes: its action has always
      been to (re)build vignettes and never omitted them.

      R CMD check accepts --no-build-vignettes as a preferred synonym
      for --no-rebuild-vignettes.

  DEPRECATED AND DEFUNCT:

    • The ENCODING argument to .C() is defunct.  Use iconv() instead.

    • The .Internal(eval.with.vis) non-API function has been removed.

    • Support for the converters for use with .C() has been removed,
      including the oft misused non-API header R_ext/RConverters.h.

    • The previously deprecated uses of array() with a 0-length dim
      argument and tapply() with a 0-length INDEX list are now errors.

    • Translation packages are defunct.

    • Calling rep() or rep.int() on a pairlist or other non-vector
      object is now an error.

    • Several non-API entry points have been transferred to packages
      (e.g. R_zeroin2) or replaced by different non-API entry points
      (e.g. R_tabulate).

    • The ‘internal’ graphics device invoked by
      .Call("R_GD_nullDevice", package = "grDevices") has been removed:
      use pdf(file = NULL) instead.

    • The .Fortran() entry point "dqrls" which has not been used by R
      since version 2.15.1 is no longer available.

    • Functions traceOn() and traceOff() in package methods are now
      defunct.

    • Function CRAN.packages() is finally defunct.

    • Use of col2rgb(0) is defunct: use par("bg") or NA instead.

    • The long-defunct functions Rd_parse(), anovalist.lm(),
      categpry(), clearNames(), gammaCody(), glm.fit.null(),
      lm.fit.null(), lm.wfit.null(), manglePackageNames(),
      mauchley.test(), package.contents(), print.coefmat(),
      reshapeLong(), reshapeWide(), tkclose(), tkcmd(), tkfile.dir(),
      tkfile.tail(), tkopen(), tkputs(), tkread(), trySilent() and
      zip.file.extract() have been removed entirely (but are still
      documented in the help system).

    • The unused dataPath argument to attachNamespace() has been
      removed.

    • grid.prompt() has been removed: use devAskNewPage() instead.

    • The long-deprecated intensities component is no longer returned
      by hist().

    • mean() for data frames and sd() for data frames and matrices are
      defunct.

    • chol(pivot = FALSE, LINPACK = TRUE), ch2inv(LINPACK = TRUE),
      eigen(EISPACK = TRUE), solve(LINPACK = TRUE) and svd(LINPACK =
      TRUE) are defunct: LAPACK will be used, with a warning.

    • The keep.source argument to library() and require() is defunct.
      This option needs to be set at install time.

    • Documentation for real(), as.real() and is.real() has been moved
      to ‘defunct’ and the functions removed.

    • The maxRasters argument of pdf() (unused since R 2.14.0) has been
      removed.

    • The unused fontsmooth argument has been removed from the quartz()
      device.

    • All the (non-API) EISPACK entry points in R have been removed.

    • chol(pivot = TRUE, LINPACK = TRUE) is deprecated.

    • The long-deprecated use of \synopsis in the Usage section of .Rd
      files will be removed in R 3.1.0.

    • .find.package() and .path.package() are deprecated: only the
      public versions without the dot have ever been in the API.

    • In a package's DESCRIPTION file,
      
          License: X11

      is deprecated, since it includes ‘Copyright (C) 1996 X
      Consortium’ which cannot be appropriate for a current R package.
      Use ‘MIT’ or ‘BSD_2_clause’ instead.

  CODE MIGRATION:

    • The C code underlying base graphics has been migrated to the
      graphics package (and hence no longer uses .Internal() calls).

    • Most of the .Internal() calls used in the stats package have been
      migrated to C code in that package.

      This means that a number of .Internal() calls which have been
      used by packages no longer exist, including .Internal(cor)
      .Internal(cov), .Internal(optimhess) and
      .Internal(update.formula).

    • Some .External() calls to the base package (really to the R
      executable or shared library) have been moved to more appropriate
      packages.  Packages should not have been using such calls, but
      some did (mainly those used by integrate()).

  PACKAGE parallel:

    • There is a new function mcaffinity() which allows getting or
      setting the CPU affinity mask for the current R process on
      systems that supports this (currently only Linux has been tested
      successfully).  It has no effect on systems which do not support
      process affinity.  Users are not expected to use this function
      directly (with the exception of fixing libraries that break
      affinity settings like OpenBLAS) - the function is rather
      intended to support affinity control in high-level parallel
      functions.  In the future, R may supplement lack of affinity
      control in the OS by its own bookkeeping via mcaffinity() related
      to processes and threads it spawns.

    • mcparallel() has a new argument mc.affinity which attempts to set
      the affinity of the child process according to the specification
      contained therein.

    • The port used by socket clusters is chosen randomly: this should
      help to avoid clashes observed when two users of a multi-user
      machine try to create a cluster at the same time.  To reproduce
      the previous behaviour set environment variable R_PARALLEL_PORT
      to 10187.

  C-LEVEL FACILITIES:

    • There has been some minor re-organization of the non-API header
      files.  In particular, Rinternals.h no longer includes the
      non-API header R_exts/PrtUtil.h, and that no longer includes
      R_exts/Print.h.

    • Passing NULL to .C() is now an error.

    • .C() and .Fortran() now warn if "single" arguments are used with
      DUP = FALSE, as changes to such arguments are not returned to the
      caller.

    • C entry points R_qsort and R_qsort_I now have start and end as
      size_t to allow them to work with longer vectors on 64-bit
      platforms.  Code using them should be recompiled.

    • A few recently added C entry points were missing the remapping to
      Rf_, notably [dpq]nbinom_mu.

    • Some of the interface pointers formerly available only to R.app
      are now available to front-ends on all Unix-alikes: one has been
      added for the interface to View().

    • PACKAGE = "" is now an error in .C() etc calls: it was always
      contrary to the documentation.

    • Entry point rcont2 has been migrated to package stats and so is
      no longer available.

    • R_SVN_REVISION in Rversion.h is now an integer (rather than a
      string) and hence usable as e.g.  #if R_SVN_REVISION < 70000.

    • The entry points rgb2hsv and hsv2rgb have been migrated to
      package grDevices and so are no longer available.

    • R_GE_version has been increased to 10 and name2col removed (use
      R_GE_str2col instead).  R internal colour codes are now defined
      using the typedef rcolor.

    • The REPROTECT macro now checks that the protect index is valid.

    • Several non-API entry points no longer used by R have been
      removed, including the Fortran entry points chol, chol2inv, cg,
      ch and rg, and the C entry points Brent_fmin, fft_factor and
      fft_work.

    • If a .External call is registered with a number of arguments
      (other than -1), the number of arguments passed is checked for
      each call (as for other foreign function calls).

    • It is now possible to write custom connection implementations
      outside core R using R_ext/Connections.h.  Please note that the
      implementation of connections is still considered internal and
      may change in the future (see the above file for details).

  INTERNATIONALIZATION:

    • The management of translations has been converted to R code: see
      ?tools::update_pkg_po.

    • The translations for the R interpreter and RGui.exe are now part
      of the base package (rather than having sources in directory po
      and being installed to share/locale).  Thus the base package
      supports three translation domains, R-base, R and RGui.

    • The compiled translations which ship with R are all installed to
      the new package translations for easier updating.  The first
      package of that name found on .libPaths() at the start of the R
      session will be used.  (It is possible messages will be used
      before .libPaths() is set up in which case the default
      translations will be used: set environment variable
      R_TRANSLATIONS to point to the location of the intended
      translations package to use this right from the start.)

    • The translations form a separate group in the Windows installer,
      so can be omitted if desired.

    • The markup for many messages has been changed to make them easier
      to translate, incorporating suggestions from Łukasz Daniel.

  INSTALLATION:

    • There is again support for building without using the C ‘long
      double’ type.  This is required by C99, but system
      implementations can be slow or flawed.  Use configure option
      --disable-long-double.

    • make pdf and make install-pdf now make and install the full
      reference index (including all base and recommended packages).

    • The 'reference manual' on the Windows GUI menu and included in
      the installer is now the full reference index, including all base
      and recommended packages.

    • R help pages and manuals have no ISBNs because ISBN rules no
      longer allow constantly changing content to be assigned an ISBN.

    • The Windows installer no longer installs a Start Menu link to the
      static help pages; as most pages are generated dynamically, this
      led to a lot of broken links.

    • Any custom settings for Java configuration are recorded in file
      etc/javaconf for subsequent use by R CMD javareconf.

    • There is now support for makeinfo version 5.0 (which requires a
      slightly different .texi syntax).

    • The minimum versions for --use-system-zlib and --use-system-pcre
      are now tested as 1.2.5 and 8.10 respectively.

    • On Windows, the stack size is reduced to 16MB on 32-bit systems:
      misguided users were launching many threads without controlling
      the stack size.

    • configure no longer looks for file ~/.Rconfig: ~/.R/config has
      long been preferred.

  BUG FIXES:

    • When R CMD build is run in an encoding other than the one
      specified in the package's DESCRIPTION file it tries harder to
      expand the authors@R field in the specified encoding.  (PR#14958)

    • If R CMD INSTALL is required to expand the authors@R field of the
      DESCRIPTION file, it tries harder to do so in the encoding
      specified for the package (rather than using ASCII escapes).

    • Fix in package grid for pushing a viewport into a layout cell,
      where the layout is within a viewport that has zero physical
      width OR where the layout has zero total relative width (likewise
      for height).  The layout column widths (or row heights) in this
      case were being calculated with non-finite values.  (Reported by
      Winston Chang.)

    • solve(A, b) for a vector b gave the answer names from colnames(A)
      for LINPACK = TRUE but not in the default case.

    • La.svd() accepts logical matrices (as documented, and as svd()
      did).

    • legend() now accepts negative pch values, in the same way
      points() long has.

    • Parse errors when installing files now correctly display the name
      of the file containing the bad code.

    • In Windows, tcltk windows were not always properly constructed.
      (PR#15150)

    • The internal functions implementing parse(), tools::parseLatex()
      and tools::parse_Rd() were not reentrant, leading to errors in
      rare circumstances such as a garbage collection triggering a
      recursive call.

    • Field assignments in reference class objects via $<- were not
      being checked because the magic incantation to turn methods on
      for that primitive operator had been inadvertently omitted.

    • setHook(hookname, value, action="replace") set the hook to be the
      value, rather than a list containing the value as documented.
      (PR#15167)

    • If a package used a NEWS.Rd file, the main HTML package index
      page did not link to it.  (Reported by Dirk Eddelbuettel.)

    • The primitive implementation of @<- was not checking the class of
      the replacement.  It now does a check, quicker but less general
      than slot<-. See the help.

    • split(x, f) now recycles classed objects x in the same way as
      vectors.  (Reported by Martin Morgan.)

    • pbeta(.28, 1/2, 2200, lower.tail=FALSE, log.p=TRUE) is no longer
      -Inf; ditto for corresponding pt() and pf() calls, such as pt(45,
      df=5000, lower.tail=FALSE, log.p=TRUE). (PR#15162)

    • The Windows graphics device would crash R if a user attempted to
      load the graphics history from a variable that was not a saved
      history. (PR#15230)

    • The workspace size for the predict() method for loess() could
      exceed the maximum integer size.  (Reported by Hiroyuki
      Kawakatsu.)

    • ftable(x, row.vars, col.vars) now also works when the *.vars
      arguments are (integer or character vectors) of length zero.

    • Calling cat() on a malformed UTF-8 string could cause the Windows
      GUI to lock up. (PR#15227)

    • removeClass(cc) gave "node stack overflow" for some class
      definitions containing "array" or "matrix".

CHANGES in previous versions:

  • Older news can be found in text format in files {NEWS.0, NEWS.1 and
    NEWS.2 in the R home directory.  News in HTML format for R versions
    from 2.10.0 to 2.15.3 is in doc/html/NEWS.2.html.

