This file records noteworthy changes.
+0.9.1 (<date>)
+* New functions/methods:
+ - remove_first() and remove_last() for lists
+ - symmetrize_cyclic()
+* Instead of just totally symmetric or antisymmetric, complex symmetries
+ can now be defined for indexed objects. Symmetries are described by a
+ tree of "symmetry" objects that is constructed with the sy_none(),
+ sy_symm(), sy_anti() and sy_cycl() functions. The symmetry of a function
+ with respect to its arguments can also be defined (this is currently
+ only used for the Beta function).
+* color_trace() and dirac_trace() can be applied to a more general class
+ of expressions, e.g. using it on a relation will take the trace on both
+ sides etc.
+* Generalized map() to take a function object instead of a function pointer.
+ This allows passing an arbitrary number of additional state to the
+ function being called.
+
+0.9.0 (7 June 2001)
+* In the output and in ginsh, lists are now delimited by { } braces, and
+ matrices are delimited by single [ ] brackets.
+* simplify_indexed() renames dummy indices so, e.g., "a.i*a.i+a.j*a.j" gets
+ simplified to "2*a.i*a.i" (or "2*a.j*a.j").
+* New functions/methods:
+ - canonicalize_clifford() (helpful when comparing expressions containing
+ Dirac matrices)
+ - symmetrize() and antisymmetrize()
+ - numer_denom() (return numerator and denominator in one call)
+ - map() (apply function to subexpressions)
+ - evalm() (evaluate sums, products and integer powers of matrices)
+* Added a new function match() for performing pattern matching. subs() and
+ has() also accept patterns as arguments. A pattern can be any expression,
+ optionally containing wildcard objects. These are constructed with the
+ call "wild(<unsigned>)" and are denoted as "$0", "$1" etc. in the output
+ and in ginsh.
+* Positive integer powers of non-commutative expressions (except matrices)
+ are automatically expanded.
+* Removed cint subdirectory, ginaccint is a separate package now due to
+ packaging considerations.
+* Several little bugfixes.
+
+0.8.3 (11 May 2001)
+* color and clifford classes are functional and documented.
+* New "spinidx" class for dotted/undotted indices.
+* Predefined spinor metric tensor (created by spinor_metric()).
+* Symbols can have a LaTeX name, e.g. symbol s("s", "\\sigma");
+* LaTeX output of indexed objects is much nicer.
+* Fixed some build problems (with recent libreadline).
+* Semantics of arithmetic operators now follows the C++ rules more strictly.
+
0.8.2 (24 April 2001)
* degree(), ldegree(), coeff(), lcoeff(), tcoeff() and collect() work with
non-symbols as the second argument in ginsh.