galib revision history.htm

提供了遗传算法的一些代码库文件

<UL>
  <LI>Project files are (finally) available for metrowerks and borland 
  compilers. Others will appear as I get them. 
  <LI>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). 
  <LI>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). 
  <LI>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). 
  <LI>A new revision, Revision B, of the PostScript documentation. 
  <LI>Fixed a problem in the statistics object that caused it to record the 
  wrong scores when minimizing the objective. 
  <LI>Fixed the scaling, statistics, and population objects to handle large 
  objective scores properly (scores that are near FLT_MAX and/or FLT_MIN). 
  <LI>Major cleanup of the MacOS and DOS/Windows versions of GAlib. Installation 
  is an order of magnitude easier. 
  <LI>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). 
  <LI>Fixed the simple genetic algorithm class to do elitism properly when 
  minimizing. 
  <LI>Added virtual destructors to the Node and NodeBASE classes so that derived 
  node classes will work properly. 
  <LI>Fixed the formating problems in the DOS/Windows package, including both 
  the end-of-line characters and the GIF images. </LI></UL><STRONG>Changes in 
version 2.4</STRONG><BR><I>released 3 June 1996</I><BR>
<UL>
  <LI>The base genetic algorithm class, 'GA', was renamed to 
  'GAGeneticAlgorithm' 
  <LI>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. 
  <LI>The 'score' member of the genome can now be used on const genomes. 
  <LI>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. 
  <LI>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). 
  <LI>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. 
  <LI>GASUSSelector was renamed to GAUniformSelector 
  <LI>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. 
  <LI>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). 
  <LI>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). 
  <LI>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. 
  <LI>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. 
  <LI>Template classes now have default operators whereever they can be defined 
  - no more ARRAY_TYPE or LIST_TYPE. 
  <LI>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]. 
  <LI>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') 
  <LI>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. 
  <LI>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. 
  <LI>Error handling has been improved a little. Error messages are now sent to 
  a GAlib error message handler. You can override the library's error handler to 
  redirect (or ignore) the messages as you see fit. 
  <LI>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). 
  <LI>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. 
  <LI>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. 
  <LI>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. 
  <LI>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. 
  <LI>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). 
  <LI>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. 
  <LI>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. 
  <LI>A new object, BoundsSet, has been defined to work with the bounded array 
  genome types. It behaves much like an allele set. 
  <LI>The constants for tree and list return codes have been rolled into their 
  respective objects to reduce namespace clutter. 
  <LI>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. 
  <LI>I made a number of changes to typedef names to make things more 
  consistent. These changes include: 
  <UL>
    <LI>'GAInitializationOperator' is now 'GAGenome::Initializer' 
    <LI>'GAMutationOperator' is now 'GAGenome::Mutator' 
    <LI>'GADistanceFunction' is now 'GAGenome::Comparator' </LI></UL>
  <LI>Changed name of 'GAReplacementGA' to 'GAIncrementalGA'. The functionality 
  of this genetic algorithm type has not changed. 
  <LI>Changed the name of 'types.h' to 'gatypes.h' to avoid conflicts with the 
  system types.h file on many platforms. 
  <LI>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. 
  <LI>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 <A 
  href="http://lancet.mit.edu/ga/Bugs.html">bugs</A> page. 
  <LI>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 <A 
  href="http://lancet.mit.edu/ga/Bugs.html">bugs</A> page. 
  <LI>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. 
  <LI>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. 
</LI></UL><STRONG>Changes in version 2.3.2</STRONG><BR><I>released 21 September 
1995</I><BR><A href="http://lancet.mit.edu/ga/API232.html">programming 
interface</A><BR>
<UL>
  <LI>Added Borland makefile and project files for the DOS distribution (in a 
  projects directory) and a Metrowerks library project file and examples project 
  stationary file for the Mac distribution (in a projects directory). 
  <LI>Made the replacement method for SteadyStateGA customizable in the same 
  manner as the ReplacementGA. You can now specify gaReplaceBest, 
  gaReplaceWorst, gaReplaceRandom, or gaReplaceCustom (or crowding) for the 
  SteadyState GA. gaReplaceParent still only works with the ReplacementGA. Fixed 
  a bug in the ReplacementGA that prevented some custom replacement schemes from 
  working properly. 
  <LI>Added the TAIL flag for doing inserts on lists. Now you can specify that a 
  new node should be inserted at the tail of the list directly instead of 
  popping down the list to the tail then doing your insert.