This blog is updated daily.
A general description is here.
The radix sort algorithm and implementation from data.table (forder) replaces the existing but limited radix (counting) sort and adds a new method for ‘order()’. Contributed by Matt Dowle and Arun Srinivasan, the new algorithm supports logical, integer (even with large values), real, and character vectors. It outperforms all other methods, but there are some caveats (see ‘?sort’).
There is a new macro, ‘USE_CXX_HEADERS’, which if set causes R headers
such as ‘R.h’ and ‘Rmath.h’ when called from C++ code in packages to
include the C++ versions of system headers such as ‘<cmath>’ rather
than the C versions. (Header ‘Rinternals.h’ always did.)
This is currently optional but is intended to become the default before release. The manual has long said that R headers should *not* be included within an ‘extern "C"’ block, and this change increases the chance of compilation errors if that is done.
When R headers such as ‘R.h’ and ‘Rmath.h’ are called from C++ code in packages they include the C++ versions of system headers such as ‘<cmath>’ rather than the legacy headers such as ‘<math.h>’. (Header ‘Rinternals.h’ already did, and inclusion of system headers can still be circumvented by defining ‘NO_C_HEADERS’, including as from this version for ‘Rinternals.h’.)
The manual has long said that R headers should *not* be included within an ‘extern "C"’ block, and almost all the packages affected by this change are doing so.
Including header ‘S.h’ from C++ code will fail on some platforms, and so gives a compilation warning on all.
‘withCallingHandler()’ now (again) handles warnings even during S4
generic's argument evaluation. (PR#16111)
‘dummy.coef.lm()’ now works in more cases, thanks to a proposal by Werner Stahel (PR#16665). In addition, it now works for multivariate linear models (‘"mlm"’, ‘manova’) thanks to a propsal by Daniel Wollschlaeger.
The ‘make’ macro ‘AWK’ which is long unused by R itself but recorded in file ‘etc/Makeconf’ is deprecated and will be removed in R 3.3.0.
The C header file ‘S.h’ is no longer documented: its use should be replaced by ‘R.h’.
‘withCallingHandler()’ now (again) handles warnings even during S4 generic's argument evaluation. (PR#16111)