R

R started as an alternative (different implementation) of Bell Laboratories' S language, but has grown into its own form and gained its separate followers.

It compiles and runs on all major OSes.

What is new in this release:

• source() now uses withVisible() rather than .Internal(eval.with.vis). This sometimes alters tracebacks slightly.
• install.packages("pkg_version.tgz") on Mac OS X now has sanity checks that this is actually a binary package (as people have tried it with incorrectly named source packages).
• splineDesign() and spline.des() in package splines have a new option sparse which can be used for efficient construction of a sparse B-spline design matrix (via Matrix).
• norm() now allows type = "2" (the ‘spectral' or 2-norm) as well, mainly for didactical completeness.
• pmin() and pmax()) now also work when one of the inputs is of length zero and others are not, returning a zero-length vector, analogously to, say, +.
• colorRamp() (and hence colorRampPalette()) now also works for the boundary case of just one color when the ramp is flat.
• qqline() has new optional arguments distribution, probs and qtype, following the example of lattice's panel.qqmathline().
• .C() gains some protection against the misuse of character vector arguments. (An all too common error is to pass character(N), which initializes the elements to "", and then attempt to edit the strings in-place, sometimes forgetting to terminate them.)
• Calls to the new function globalVariables() in package utils declare that functions and other objects in a package should be treated as globally defined, so that CMD check will not note them.
• print(packageDescription(*)) trims the Collate field by default.
• The included copy of zlib has been updated to version 1.2.7.
• A new option "show.error.locations" has been added. When set to TRUE, error messages will contain the location of the most recent call containing source reference information. (Other values are supported as well; see ?options.)

What is new in version 3.2.1 / 3.2.2-prerelease:

• source() now uses withVisible() rather than .Internal(eval.with.vis). This sometimes alters tracebacks slightly.
• install.packages("pkg_version.tgz") on Mac OS X now has sanity checks that this is actually a binary package (as people have tried it with incorrectly named source packages).
• splineDesign() and spline.des() in package splines have a new option sparse which can be used for efficient construction of a sparse B-spline design matrix (via Matrix).
• norm() now allows type = "2" (the ‘spectral' or 2-norm) as well, mainly for didactical completeness.
• pmin() and pmax()) now also work when one of the inputs is of length zero and others are not, returning a zero-length vector, analogously to, say, +.
• colorRamp() (and hence colorRampPalette()) now also works for the boundary case of just one color when the ramp is flat.
• qqline() has new optional arguments distribution, probs and qtype, following the example of lattice's panel.qqmathline().
• .C() gains some protection against the misuse of character vector arguments. (An all too common error is to pass character(N), which initializes the elements to "", and then attempt to edit the strings in-place, sometimes forgetting to terminate them.)
• Calls to the new function globalVariables() in package utils declare that functions and other objects in a package should be treated as globally defined, so that CMD check will not note them.
• print(packageDescription(*)) trims the Collate field by default.
• The included copy of zlib has been updated to version 1.2.7.
• A new option "show.error.locations" has been added. When set to TRUE, error messages will contain the location of the most recent call containing source reference information. (Other values are supported as well; see ?options.)

What is new in version 3.2.1:

• source() now uses withVisible() rather than .Internal(eval.with.vis). This sometimes alters tracebacks slightly.
• install.packages("pkg_version.tgz") on Mac OS X now has sanity checks that this is actually a binary package (as people have tried it with incorrectly named source packages).
• splineDesign() and spline.des() in package splines have a new option sparse which can be used for efficient construction of a sparse B-spline design matrix (via Matrix).
• norm() now allows type = "2" (the ‘spectral' or 2-norm) as well, mainly for didactical completeness.
• pmin() and pmax()) now also work when one of the inputs is of length zero and others are not, returning a zero-length vector, analogously to, say, +.
• colorRamp() (and hence colorRampPalette()) now also works for the boundary case of just one color when the ramp is flat.
• qqline() has new optional arguments distribution, probs and qtype, following the example of lattice's panel.qqmathline().
• .C() gains some protection against the misuse of character vector arguments. (An all too common error is to pass character(N), which initializes the elements to "", and then attempt to edit the strings in-place, sometimes forgetting to terminate them.)
• Calls to the new function globalVariables() in package utils declare that functions and other objects in a package should be treated as globally defined, so that CMD check will not note them.
• print(packageDescription(*)) trims the Collate field by default.
• The included copy of zlib has been updated to version 1.2.7.
• A new option "show.error.locations" has been added. When set to TRUE, error messages will contain the location of the most recent call containing source reference information. (Other values are supported as well; see ?options.)

What is new in version 3.2.0 / 3.2.1-prerelease:

• source() now uses withVisible() rather than .Internal(eval.with.vis). This sometimes alters tracebacks slightly.
• install.packages("pkg_version.tgz") on Mac OS X now has sanity checks that this is actually a binary package (as people have tried it with incorrectly named source packages).
• splineDesign() and spline.des() in package splines have a new option sparse which can be used for efficient construction of a sparse B-spline design matrix (via Matrix).
• norm() now allows type = "2" (the ‘spectral' or 2-norm) as well, mainly for didactical completeness.
• pmin() and pmax()) now also work when one of the inputs is of length zero and others are not, returning a zero-length vector, analogously to, say, +.
• colorRamp() (and hence colorRampPalette()) now also works for the boundary case of just one color when the ramp is flat.
• qqline() has new optional arguments distribution, probs and qtype, following the example of lattice's panel.qqmathline().
• .C() gains some protection against the misuse of character vector arguments. (An all too common error is to pass character(N), which initializes the elements to "", and then attempt to edit the strings in-place, sometimes forgetting to terminate them.)
• Calls to the new function globalVariables() in package utils declare that functions and other objects in a package should be treated as globally defined, so that CMD check will not note them.
• print(packageDescription(*)) trims the Collate field by default.
• The included copy of zlib has been updated to version 1.2.7.
• A new option "show.error.locations" has been added. When set to TRUE, error messages will contain the location of the most recent call containing source reference information. (Other values are supported as well; see ?options.)

What is new in version 3.2.0:

• source() now uses withVisible() rather than .Internal(eval.with.vis). This sometimes alters tracebacks slightly.
• install.packages("pkg_version.tgz") on Mac OS X now has sanity checks that this is actually a binary package (as people have tried it with incorrectly named source packages).
• splineDesign() and spline.des() in package splines have a new option sparse which can be used for efficient construction of a sparse B-spline design matrix (via Matrix).
• norm() now allows type = "2" (the ‘spectral' or 2-norm) as well, mainly for didactical completeness.
• pmin() and pmax()) now also work when one of the inputs is of length zero and others are not, returning a zero-length vector, analogously to, say, +.
• colorRamp() (and hence colorRampPalette()) now also works for the boundary case of just one color when the ramp is flat.
• qqline() has new optional arguments distribution, probs and qtype, following the example of lattice's panel.qqmathline().
• .C() gains some protection against the misuse of character vector arguments. (An all too common error is to pass character(N), which initializes the elements to "", and then attempt to edit the strings in-place, sometimes forgetting to terminate them.)
• Calls to the new function globalVariables() in package utils declare that functions and other objects in a package should be treated as globally defined, so that CMD check will not note them.
• print(packageDescription(*)) trims the Collate field by default.
• The included copy of zlib has been updated to version 1.2.7.
• A new option "show.error.locations" has been added. When set to TRUE, error messages will contain the location of the most recent call containing source reference information. (Other values are supported as well; see ?options.)

What is new in version 3.1.3 / 3.2.0-prerelease:

• source() now uses withVisible() rather than .Internal(eval.with.vis). This sometimes alters tracebacks slightly.
• install.packages("pkg_version.tgz") on Mac OS X now has sanity checks that this is actually a binary package (as people have tried it with incorrectly named source packages).
• splineDesign() and spline.des() in package splines have a new option sparse which can be used for efficient construction of a sparse B-spline design matrix (via Matrix).
• norm() now allows type = "2" (the ‘spectral' or 2-norm) as well, mainly for didactical completeness.
• pmin() and pmax()) now also work when one of the inputs is of length zero and others are not, returning a zero-length vector, analogously to, say, +.
• colorRamp() (and hence colorRampPalette()) now also works for the boundary case of just one color when the ramp is flat.
• qqline() has new optional arguments distribution, probs and qtype, following the example of lattice's panel.qqmathline().
• .C() gains some protection against the misuse of character vector arguments. (An all too common error is to pass character(N), which initializes the elements to "", and then attempt to edit the strings in-place, sometimes forgetting to terminate them.)
• Calls to the new function globalVariables() in package utils declare that functions and other objects in a package should be treated as globally defined, so that CMD check will not note them.
• print(packageDescription(*)) trims the Collate field by default.
• The included copy of zlib has been updated to version 1.2.7.
• A new option "show.error.locations" has been added. When set to TRUE, error messages will contain the location of the most recent call containing source reference information. (Other values are supported as well; see ?options.)

What is new in version 2.9.1:

• New function anyDuplicated(x) returns 0 (= FALSE) or the index of the first duplicated entry of x.
• matplot(), matlines() and matpoints() now also obey a 'lend' argument, determining line end styles.
• bw.SJ(), bw.bcv() and bw.ucv() now gain an optional 'tol' argument allowing more accurate estimates.
• new.packages() no longer regards packages with the same name as a member of an installed bundle as 'new' (this is now consistent with the dependency checks in install.packages()).
• It no longer reports on partially installed bundles (since members can be updated individually if a bundle is unbundled).
• old.packages() and hence updates.packages() will look for updates to members of package bundles before updates to the whole bundle: this allow bundles to be split and installations updated.
• nlminb() gives better non-convergence messages in some cases.
• S3 method dispatch will support S4 class inheritance for S3 methods, for primitives and via UseMethod(), if the argument S3methods=TRUE is given to setClass(). S4 method dispatch will use S3 per-object inheritance if S3Class() is set on the object. See ?Methods and the paper referenced there.
• R CMD INSTALL is more tolerant of (malformed) packages with a 'man' directory but no validly named .Rd files.
• R CMD check now reports where options are used that cause some of the checks to be skipped.
• RSiteSearch has been updated to be consistent with the new layout of the search site itself, which now includes separate options for vignettes, views, and r-sig-mixed-models, as well as changed names for r-help.
• That R CMD check makes use of a <pkg>/tests/Examples/<pkg>-Ex.Rout.save file as a reference result is now documented in 'Writing R Extensions'.