=head1 Changes

2004/06/14 1.21 Minor documentation corrections.                         

2004/06/10 1.20 Capitalized module file names correctly.                 

2004/06/09 1.19 Lib, Pod cleanup                                         

2004/06/08 Observed transit of Venus in room converted to Camera Obscura.

2004/06/04 1.18 Equation simplification tied to += operator              

2004/06/02 1.17 Following further excellent suggestions from Mike Schilli
slightly improved notation for equation solving:

B<eq> is a synonym for B<-> 

B<E<gt>> is a synonym for B<solve()>

Thus: 

  $x      = symbols('x');
 ($a, $b) =  @{ ($x**2 eq 5*$x+6) > $x };  

  print "$a,$b\n";

 # 2,3


2004/06/01 1.16 Following excellent suggestions from Mike Schilli detect
constants with decimal places and convert them to rational fractions,
thus 1.2 becomes 12/10. The rationale: using fractions avoids loss of
precision, if you only need approximate numerical results, there is no
need for symbolic manipulations.

2004/05/28 1.15 Minor changes to documentation.

2004/05/27 1.14 Admiring new CPAN Layout: diff+grep. Updated META.yml
requires/recommends to match MANIFEST.  Removed use of Hash::Util
as this seems to be causing problems with ActiveState.

2004/05/11 1.13 Memory Leak and B<exp()> problems solved:

1. Solved a memory leak by using Scalar::Util::weaken(). This has
reduced memory consumption when running the test cases from 130M to 37M:
intermediate expressions are now being freed. I believe that this has
been the source of the erratic failures on various platforms, other than
my development system, as reported (most helpfully) by CPAN testers and
a Mac OSX user: these reported errors appear to have been related to
running out of memory.

2. Corrected B<exp(-i)*exp(-i)> which was being correctly reduced to
B<exp(0)>, but should have been reduced further to B<1>, which was
causing the multiply out of B<exp(i...)> in B<cot(x) == 1/tan(x)> to fail.

3. Added the != operator, as this simplifies testing with the test
harness.

2004/04/30 1.12 Included PREREQ_PM in Makefile as a result of notes from
automated CPAN testing.

2004/04/24 1.08 Included test cases in manifest and renamed to .t in
line with observed practice.

2004/03/28 Split into three classes.  Considerable performance
improvements.  Added standard Perl Test harness.  Unfixed power()
so we are back to constant powers.

2004/03/14 Fixed power() so that it recognizes constant and variable
powers. Added TODO List. Finished testSM(): new requirements in TODO.

2004/03/13 Added change log on esteemed advice of Steffen Müller. Made
yet another attempt to stop polynomialDivide() from producing an
infinite series as a representation of a single term. Most of
mathematics seems to erupt from the division of one polynomial by
another.

=cut