* Tidied some old crap.

[ginac.git] / NEWS

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 This file records noteworthy changes.
 
-0.6.5 ()
+0.8.0 (<date>)
+* Complete revamp of indexed objects. Instead of multiple classes for
+  indexed things and their indices there is now only one "indexed" class
+  and two types of indices: "idx" for simple indices and "varidx" for
+  indices with variance. There are predefined delta, epsilon and metric
+  tensors, and a function simplify_indexed() that performs canonicalization
+  and dummy index summations. Matrix objects can be indexed for doing simple
+  linear algebra.
+* Added an option "expand_indexed" to expand() to perform expansion of
+  indexed objects like (a+b).i -> a.i + b.i
+* Renamed get_indices() to get_free_indices(), which no longer returns
+  dummy indices and checks the consistency of indices in sums.
+* sqrfree() factorization fixed and improved syntactically.
+* subs() works on matrices.
+* Matrices can be constructed from flat list of elements; diagonal matrices
+  can be constructed from list of diagonal elements with diag_matrix()
+* Fixed memory leak in expand().
+* Operator% for objects of class ncmul has gone.  Use operator* now for that
+  case too, which is much more natural.
+
+0.7.3 (28 February 2001)
+* Several bugfixes and minor performance tunings.
+* Added a section to the tutorial about adding new algebraic classes to GiNaC.
+* Closed many in-source documentation gaps.
+
+0.7.2 (17 February 2001)
+* Several bugfixes in power series expansion, one of them critical.
+
+0.7.1 (7 February 2001)
+* Fix problems with Cint that were caused by CLN's overloaded operator new.
+* Fix compilation errors with GCC3.
+* normal() handles large sums of fractions better and normalizes the exponent
+  of power expressions.
+* expand() always expands the exponent and transforms x^(a+b) -> x^a*x^b.
+* Some bugfixes of series expansion around branch cuts of special functions.
+
+0.7.0 (15 December 2000)
+* Requires CLN 1.1 now.  Class numeric doesn't use an indirect pointer to the
+  actual representation any more.  This is a speedup.
+* mul::expand() was reengineered to not allocate excess temporary memory.
 * Non-integer powers of a symbol are treated as constants by (l)degree() and
-  coeff(). Using these functions on an expression containing such powers used
-  to fail with an internal error message. The side-effect is that collect()
+  coeff().  Using these functions on an expression containing such powers used
+  to fail with an internal error message.  The side-effect is that collect()
   can be used on expressions which are not polynomials.
 * Added a man page for the ginac-config script.
+* Ctor of numeric from char* honors Digits.
 
 0.6.4 (10 August 2000)
 * Complete revamp of methods in class matrix.  Some redundant (and poor)