release notes for GAlib

2.4.6 January 2005
-------------------------------------------------------------------------------
Updated tspview and gaview graphic examples in the examples/graphic directory.
These now build cleanly out-of-the-box on linux (and other) unix systems that
have X windows.  The options for building with MOTIF widget sets (still) work
and are now the default.  Try running tspview with two different genetic 
algorithms to see how differently they behave.  For example:

  tspview ga 1           (generational)
  tspview ga 2           (crowding)
  tspview ga 3           (simple)

will give you three different windows.  Run them to see how generational,
simple, and crowding algorithms differ.  Note that the crowding algorithm
will find all of the (equally good) optimal solutions.

Updated macros in gaconfig.h to have fewer clashes with other libraries.

Much improved out-of-the-box behavior with various recent compilers, including
gcc3 and vcpp7.  Added options for building on macosx with gcc2 and gcc3.
The library is now up-to-date with respect to: gcc2, gcc3, vcpp6, vcpp7, xlC,
aCC, CC, BCC55 (that is all the compilers I have with which to test).

Split the windows makefiles into two, one for vcpp and one for borland.  The
make syntax is simply too incompatible to keep them in a single file (for now
anyway, until I find a source for the arcane behaviors of each one).  Still
to come is complete makefile support for building shared libraries - sorry,
but for now you have to do that on your own.

All galib random number generators have been change to garan* in order to avoid
naming conflicts with other libraries.  There is still only one rng at a time
and no run-time modification of the rng is possible (that is coming with 3.0).

Better inclusion of GARealGenome and GAStringGenome files for specializations.
the new method accommodates gcc3 premature instantiation quirks and makes the
code that uses the genomes slightly less cryptic.  See ex21.C to see how this
is done.

There is now a file called std_stream.h in the ga directory.  this file takes
care of the differences between various iostream naming requirements.  Some
platforms require std for the namespace, some do not.  Some require use of
<iostream.h>, others require simply <iostream>.  When you create your own code
that uses GAlib, you do not need to use the macros from std_stream.h, but they
are used in the examples so that the example code will build in any 
environment, regardless of its use of streams.

The macros for controlling use of streams are now easier to understand and use.

Fixed bug in GASelector::update that could cause memory corruption (thanks to
Giovanni Sartoni for finding this one).  Added assertions to expose any other
end-of-array problems in the selector algorithms.

Use local copy of score when calculating population statistics just in case the
genome scores change on each invocation of the score method.

The seed can now be remembered by each genetic algorithm (or passed on the fly
as before).  Only the GABaseGA class remembers the seed - derived GA classes 
do nothing with it right now.  This is so that existing behavior will not be 
changed.  Then next major release will include persistance and use of seeds
within the genetic algorithms.


2.4.5
February 2000
-------------------------------------------------------------------------------
Created a function GABin2DecPhenotype::equal(const GABin2DecPhenotype & b)
since vcpp would not recognize operator== as a friend of the phenotype class.

Removed inclusion of iostream.h from gaerror.C

Created new projects using codewarrior 5.3 on macos.  They are now included
as a separate file for download from the ftp site.

Removed USE_RTTI from gaconfig.h since it is not used (yet). 

Cleanup to the library makefiles. Separate makefiles for unix and winnt 
(no need to compile using vcpp projects anymore!) I decided not to use 
autoconf since the overhead of using autoconf outweighs the benefits 
(at least until someone makes it easier to use and modify). At this point 
i think it is easier for people to modify the makefile (or makevars) rather 
than to figure out how to use all the options to configure. 

Fixed GAGeneticAlgorithm::TerminateUponPopConvergence so that it now does the
right thing. In doing so we redefined what population convergence means. Now 
it is: min/max. When minimizing, this will stop the evolution when the value
is less that the threshhold. When maximizing, this will stop the evolution 
when the value is greather than the threshhold. The threshhold must be between
0 and 1, inclusive. Note that this method fails if the maximum objective score
might be zero. (thanks to Bill White) 

Fixed initialization bug in GAPopulation.C that could cause unitialized memory
read (thanks to Harold H Soleng of Norwegian Computing Center). 

Fixed boolean read problem in the GAParameters object 
(thanks to Klaus Kirchberg). 

Added compile-time warning message to garandom.h to help people avoid bogus 
random number generator issues. 

Fixed RNG bug in RAN1 and RAN2 (thanks to Peter Ross and George LeCompte). 

Fixed RNG bug in RAN3 (thanks to Peter Ross). 

Started putting the DLL code in, but that will have to wait until i have more
time for extensive testing. Probably that will go in when the thread-safe 
mods go in. 

Cleaned up the HTML documentation in the distribution a little bit. 

Everything is now in CVS, including the web site. 

I am no longer maintaining a separate dos distribution. 




Changes in version 2.4.4
4 April 1999
-------------------------------------------------------------------------------
Fixes to gaconfig.h to make things compile out-of-the-box a bit better for 
more platforms. 

Replaced C-style casts with dynamic_cast and friends. Macros expand to the 
old-style casts if your compiler does not support the new-style casts. 

Fixed const-ness of genomes used internally to the built-in operators. 

Added minimal support for rtti. This will be disabled if your compiler does 
not support it. 

Added support for ansi streams. You can now select whether to use ansi streams
or the older streams by defining the appropriate directive. GAlib will then 
use either the old streams headers , the ansi streams headers , or no streams 
at all. 

Changes from int to unsigned int for these functions: 
        GABin2DecPhenotype::size 
        GABin2DecPhenotype::nPhenotypes 

Many fixes to signed/unsigned conversions. For the most part, all I did was 
make them explicit using static_cast 

Added GADCrowdingGA to the library (it has been in the TSP example for a long 
time, now it is part of the library). 

Fixed questionable initialization of iterators in GATree and GAList 

The library now compiles more cleanly on vcpp, metrowerks, sgi CC, and g++ 
2.8.1 (ok, i had to disable a couple of vcpp warnings, but of what use is a 
warning that says "you're losing data converting 1.0 into a float" ?) Can 
anyone tell me what to do about g++ warnings about "variable 'xxx' might be 
clobbered by 'longjmp' or 'vfork'" ? 

Graphic examples are now included in the windows distribution: points on a 
surface and travelling salesman. Really, they are this time :) They are hacked 
together using a windows wizard (gads, what a horrible environment that is), 
but they should get you started. 

Added #undef for min/max in GAPopulation.h and GABin2Dec.h (microsoft headers 
in particular are promiscuous in their definition of min/max macros) 

Changed doubles to floats in 
        GAPopulation::scale 
        GAPopulation::statistics 

Changed template instantiation syntax in GARealGenome.C and GAStringGenome.C 




Changes in version 2.4.3
11 November 1998
-------------------------------------------------------------------------------
Graphic examples for mac 

Graphic examples for windows 

Fixed example 13 to actually do what it claimed to do. Beware that it may run
for a really long time now (it has a GA embedded in another GA, so each 
evaluation results in another GA run). 

Fixed gaversion.h to accurately record the library version (for better use 
with ident) 

Added definition of M_PI to the examples in which that macro is used (some 
platforms do not have M_PI defined in their math headers) 

Fixed bug in GAAlleleSet<>::allele() that caused upper/lower bounds to be 
generated when they should not have been. Note that your initialize, 
crossover, mutate operators must respect allele set limit boundaries otherwise
you'll end up with bogus values. 

Fixed bugs in GADemeGA: 
        GADemeGA::nMigration did not set parameter list 
        GADemeGA::nPopulations did not set parameter list 
        GADemeGA::step set numrep incorrectly 
        GADemeGA::step looped on tmppop size rather than nrepl 
        GADemeGA::nReplacement did not update tmppop size properly 
        GADemeGA::nReplacement did not update the parameter list 
        GADemeGA::nPopulations did not update nrepl or pstats correctly 

Fixed bug in GARealGaussianMutator that caused no mutation to occur in cases 
when 100% mutation should have happened. 

Fixed bug in GAGeneticAlgorithm::TerminateUponConvergence that would cause 
the evolution to stop immediately when doing a minimization with convergence 
as the stopping criterion. 

Fixed various memory leaks 
        GAAlleleSetArray<>::remove 

Various makefile/project additions and cleanup 

New project files for Codewarrior 

New project files for MS VC++ 

Fixes to makefiles to make cross-unix compiles easier. 

Fixed html documentation: 

For the GAStatistics object, the member functions offlineMax, offlineMin, 
minEver, maxEver were incorrect. 

In GAPopulation::diversity, 1 indicates that each individual is completely 
different. 

The title of Melanie Mitchell's book had been omitted. 

Fixed mask clear bug in GA1DArrayGenome<>::CycleCrossover 

Fixed signed/unsigned problems in array genomes. As a result, the following 
member functions have been removed: 
        GA1DArrayGenome<>::operator[] 
        GA1DArrayGenome<>::operator[](int) 

Various fixes and features to random number generator 

Added chi-square tests to the randtest program for better RNG testing. 

Added GAGetRandomSeed to get the random seed from the library. 

Added GAGetRNG function to tell which RNG was compiled in. 

Fixed bug in implementation of GARandomSeed. Now the changing bits of the 
value returned by time() are correctly assimilated into the seed, even if the 
seed has fewer bits than the value returned by time(). 

Fixed bug in read member of 1D, 2D, and 3D binary string genomes. 

Added pragmas for VC++ in gaconfig.h to disable warnings. 

Fixed bug in resizeBehaviour routines in 3D genomes 

Fixed bug in example 5 and example 14 in which score cache flag was not 
properly updated. 




Changes in version 2.4.2
13 November 1996
-------------------------------------------------------------------------------
Sorry, but I lost the list due to a hard drive crash :( 




Changes in version 2.4.1
10 November 1996
-------------------------------------------------------------------------------
Project files are (finally) available for metrowerks and borland compilers. 
Others will appear as I get them. 

Fixed the constructors for 2D and 3D array allele genomes so that you can 
construct them with allele set arrays as well as allele sets. You must define 
your own initializer to take advantage of the allele set arrays, however 
(initialization using the default initializer will ignore the additional 
allele sets). 

Fixed a problem with ios::out and other stream flags in the statistics and 
parameters modules. If your compiler is ANSI standard and uses the STL streams
then you may need to use the NO_STREAMS directive to turn off the streams in 
GAlib (GAlib is not yet STL-streams compliant). 

Added blend crossover (BLX) and arithmetic crossover for real number genomes. 
An implementation of the edge recombination crossover (ERX) for list genomes 
is included in two of the examples (for the travelling salesman problems). 

A new revision, Revision B, of the PostScript documentation. 

Fixed a problem in the statistics object that caused it to record the wrong 
scores when minimizing the objective. 

Fixed the scaling, statistics, and population objects to handle large 
objective scores properly (scores that are near FLT_MAX and/or FLT_MIN). 

Major cleanup of the MacOS and DOS/Windows versions of GAlib. Installation is 
an order of magnitude easier. 

Added a graphic travelling salesman example (graphic examples are only 
available for unix versions - Mac and PC versions will come as soon as I have 
the basic code to do graphic display and rudimentary GUI on those platforms). 

Fixed the simple genetic algorithm class to do elitism properly when 
minimizing. 

Added virtual destructors to the Node and NodeBASE classes so that derived 
node classes will work properly. 

Fixed the formating problems in the DOS/Windows package, including both the 
end-of-line characters and the GIF images. 




Changes in version 2.4
released 3 June 1996
-------------------------------------------------------------------------------
The base genetic algorithm class, 'GA', was renamed to 'GAGeneticAlgorithm' 

Function prototypes for genome operators are now defined in the genome scope. 
Similarly, function prototypes for genetic algorithm and population object 
operators are defined in their respective scopes. 

The 'score' member of the genome can now be used on const genomes. 

The documentation is now distributed with GAlib. The documentation now 
contains a page illustrating how to define your own operators and derive your 
own GAlib-based classes. 

GAlib now compiles warning-free when you use the -Wall flag for the g++ 
compiler. The number of warnings when compiled with Borland, Metrowerks, and 
Symantec compilers has also been reduced (although Borland still won't let 
you inline for, while, or switch statements). 

The config.h header file now figures out as much as possible about your 
system so that you should not have to tweak it nearly as much as in previous 
releases. 
GASUSSelector was renamed to GAUniformSelector 

The GASharing object has been reworked to better match the description of 
scaling proposed by Goldberg. It now lets you select both the sigma cutoff 
and alpha values for tuning the scaling radius and importance. 

The steady-state genetic algorithm will now work properly with the sharing 
method of fitness scaling (although Goldberg typically refers to sharing in 
the context of non-overlapping populations, you can use it with overlapping 
populations if you do the replacement right). 

GAlib works with PVM 3.3.10 or later. This release of GAlib includes examples 
that show how to use GAlib with PVM for two types of parallelization: (1) one 
genome per process/CPU and (2) one population per process/CPU. I'm also 
considering an MPI example (if only there were stable C++ bindings for PVM 
and MPI). 

Parallel populations on a single CPU are now possible using the island model 
with migration rates and (custom) replacement between populations. Each 
population can have its own selection and replacement methods, independent of
 the other populations. By default all populations are clones of each other 
(same initialization, mutation, crossover, selection, replacement). The 
parallel populations are evolved using steady-state genetic algorithm model 
with user-specified overlap, etc. This is illustrated in one of the examples. 

Default and built-in operators are now defined as static member function of 
the genome classes with which they are associated. This cleans up the 
namespace quite a bit. 

Template classes now have default operators whereever they can be defined - 
no more ARRAY_TYPE or LIST_TYPE. 

The genome files have been consolidated. Rather than a bunch of files 
(typically 6) for each genome, the library uses a single pair (.h and .C) for 
each genome. For example, binstr1.[ch|xs|op].[C|h] is now simply 
binstr1.[C|h]. 

Genomes now contain an 'evaluation data' object. This is a pointer to an 
object derived from the EvalData class. Its purpose is to provide a mechanism 
for storing custom information with each genome. The userData member is 
similar in function, but whereas the userData object is the same for all 
genomes, the evalData object may be different for each genome. (the evalData 
object supercedes the 'ObjectiveVector') 

The ArrayGenome class has been restructured as ArrayGenome and 
ArrayAlleleGenome (derived from ArrayGenome). The library includes 
instantiations of char and double versions of the ArrayAlleleGenome class to 
form the StringGenome and RealGenome classes. The RealGenome class provides a 
mechanism for doing an array of bounded real numbers and/or sets of real 
numbers. Sample uniform and gaussian mutator are included for the RealGenome 
class. 

A new compile-time flag, NO_STREAMS, has been added to let you
compile-out the GAlib dependencies on the streams library. When you
compile-out the streams dependencies you cannot use the default GAlib
routines for reading from and writing to file, but the error routines
will still work properly.  

Error handling has been improved a little sages to a GAlib-specific
error handler. You can override the library's error handler to
redirect (or ignore) the messages as you see fit.  

A converter architecture has been added to the binary string
objects. GAlib contains two default converters: Gray and 

Binary encode/decode. You can use either of these or define your own
for mapping decimal values into the binary strings. The
binary-to-decimal conversions now support more bits - up to 128
(depending on the system you're running on).  

The statistics object has been cleaned up and more statistics have
been added. GAs can now flush stats periodically to file or on-demand,
and the types of stats that get recorded can be controlled. The
interface for recording scores, score buffering, and flushing to file
has been revamped.  

The parameters object has been completely overhauled. It can now read
from the command line and/or a settings file using (user definable)
strings to set the GA parameters. Since each GA contains a parameters
object, these capabilities have also been extended to the GA classes.  

The base genome class has been cleaned up. In particular, the clone
method and dimension enums have been declared in the genome scope to
reduce namespace clutter. Also changed are the read/write member
functions. They have been renamed (no underscore) and return an
integer status. The crossover interface is completely different (see
below). 

Now each genome contains a crossover hint that suggests to a GA how it
should mate. By default, the GAs use this information to do the
crossovers, but a custom GA can ignore the suggested crossover and do
its own mating if it wants to. The equal/not equal members are now
public and the underscore has been removed.  

A compare member function has been added to the genome class. This
member function (customizable) provides a mechanism for measuring the
diversity of a population.  

The CrossSite object no longer exists. A new member function,
'crossover', and two access functions, 'sexual' and 'asexual', have
taken its place. The crossover function operates on one or two
children, so the site information is no longer stored with each
genome. The new interface also defines a mechanism for doing asexual
reproduction, so it is easier now to implement GAs that use this kind
of mating. You can also define crossovers that operate on genomes with
mixed data types (this will require a special GA, but you can derive
that from one of the standard GA objects then modify the crossover
part).  

The allele set now does reference counting. This allows you to define
an allele set in a scope other than the scope in which the genome(s)
is defined. It also reduces overhead - each genome does not need to
keep its own copy of the allele set.  

Binary-to-decimal phenotypes now do reference counting. Like the
allele sets, phenotypes are needed by many genomes. But there's too
much overhead to require each genome to keep its own copy of the
phenotype. So now you can create a single phenotype (for your
prototype genome) and subsequent clones of your genome will refer to
the same phenotype, even if it goes out of scope.  

A new object, BoundsSet, has been defined to work with the bounded
array genome types. It behaves much like an allele set.  

The constants for tree and list return codes have been rolled into
their respective objects to reduce namespace clutter.  

Genome comparators now return 0 for identical genomes and greater than
0 for completely different genomes. This makes better lexical sense:
as the diversity decreases, so does the absolute measure. Notice that
previous versions of GAlib expected the opposite measure.  

I made a number of changes to typedef names to make things more
consistent. These changes include:   
        'GAInitializationOperator' is now 'GAGenome::Initializer' 
        'GAMutationOperator' is now 'GAGenome::Mutator' 
        'GADistanceFunction' is now 'GAGenome::Comparator' 

Changed name of 'GAReplacementGA' to 'GAIncrementalGA'. The
functionality of this genetic algorithm type has not changed.  

Changed the name of 'types.h' to 'gatypes.h' to avoid conflicts with
the system types.h file on many platforms.  

The selection function is now a member of the population object. The
signature has not changed, and the selection function is still
custimizable, but now housekeeping of population statistics is much
more uniform and less convoluted. This also allows you to define a
different selection method for each of the populations when using
multiple populations.  

Fixed the bug in the population copy method. The bug caused the
population to clone the worst individual multiple times rather than
cloning each individual in the population. The patch is descibed in
the bugs page.  

Changing the population size during an evolution now works without the
extra call to evaluate. Fixed the bug in the scaling object that
prevented the updates after initialization. The patch is descibed in
the bugs page.  

Lots of minor const-correctness tweaks and cleanup of the code, plus
fixes of all reported bugs. The new version is marginally faster than
the previous.  

Older versions of the library had problems when objects used by other
objects went out of scope. For example, if you created a genome using
an allele set then left the scope in which the allele set was active,
the genome would refer to garbage. These inconsistencies have been
fixed. Objects now make copies of the objects they need, but make no
more copies than necessary. There's a whole lot of reference counting
and caching going on now.