440 lines
23 KiB
HTML
440 lines
23 KiB
HTML
<!doctype html public "-//w3c//dtd html 4.0 transitional//en">
|
|
<html>
|
|
<head>
|
|
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
|
|
<meta name="GENERATOR" content="Mozilla/4.76 [en] (X11; U; Linux 2.2.17-21mdksmp i686) [Netscape]">
|
|
<title>Tutorial: Lesson 1</title>
|
|
</head>
|
|
<body text="#000000" link="#0000EE" vlink="#551A8B" alink="#FF0000" background="beige009.jpg">
|
|
<a href="eoLesson2.html">Lesson 2</a> -
|
|
<a href="eoTutorial.html">Tutorial
|
|
main page</a> -
|
|
<a href="eoTopDown.html">Algorithm-Based</a> - <a href="eoBottomUp.html">Component-Based</a>
|
|
- <a href="eoProgramming.html">Programming hints</a> -<font face="Arial,Helvetica"><font size=+1><a href="../../doc/html/index.html">EO
|
|
documentation</a></font></font>
|
|
<br>
|
|
<hr WIDTH="100%"><!-- -------------- End of header ------------------ --><!-- ----------------------------------------------- -->
|
|
<center>
|
|
<h1>
|
|
<font color="#FF0000">Tutorial: Lesson 1</font></h1></center>
|
|
This lesson will let you
|
|
<ul>
|
|
<li>
|
|
<a href="#run">run</a> your first Evolutionary Algorithm written within
|
|
EO Library, choosing between evolving <font color="#999900">bitstrings</font>,
|
|
or evolving <font color="#999900">vectors of real numbers</font>,</li>
|
|
|
|
<li>
|
|
<a href="#browse">browse</a> through the code of these algorithms, or</li>
|
|
|
|
<li>
|
|
follow the <a href="#tour">guided tour</a>.</li>
|
|
</ul>
|
|
Later you will be asked to
|
|
<ul>
|
|
<li>
|
|
<a href="#exercise1">write</a> your own <font color="#990000">fitness function</font>,</li>
|
|
|
|
<li>
|
|
<a href="#exercise2">check</a> that EO let you separate the <font color="#999900">representation</font>
|
|
from the <font color="#009900">evolution engine</font>.</li>
|
|
|
|
<li>
|
|
<a href="#exercise3">use different kinds</a> of <font color="#009900">selection
|
|
procedures</font> in the framework of a generational GA <font color="#009900">evolution
|
|
engine</font>,</li>
|
|
</ul>
|
|
|
|
<h3>
|
|
|
|
<hr WIDTH="100%"><a NAME="run"></a><font color="#000099">I want to run
|
|
an Evolutionary Algorithm
|
|
<b>now</b></font></h3>
|
|
You can choose to run a standard <a href="FirstBitGA.html">bitstring Genetic
|
|
Algorithm</a> (as defined in Goldberg's book) or a standard <a href="FirstRealGA.html">real-valued
|
|
genetic algorithm</a>, as proposed in Micahlewicz's book.
|
|
<p>If you have not already done what was recommended in the <a href="eoTutorial.html#install">Tutorial
|
|
main page</a> , do it <b><font color="#FF6600">NOW</font></b>. Then go
|
|
to the Lesson1 sub-dir of the tutorial dir, and simply type at the system
|
|
prompt
|
|
<p><tt>(myname@myhost) EOdir/Tutorial/Lesson1 % <font color="#FF6666">FirstRealGA</font></tt>
|
|
<br>or
|
|
<br><tt>(myname@myhost) EOdir/Tutorial/Lesson1 % <font color="#FF6666">FirstBitGA</font></tt>
|
|
<p>and something should happen.
|
|
<h3>
|
|
<font color="#000099">What is happening?</font></h3>
|
|
At the moment, the <font color="#FF6600">FirstBitGA</font> maximizes the
|
|
number of ones in the bitstring (also calls the <font color="#FF6600">OneMaxfunction</font>,
|
|
whose solution is, as you can guess,
|
|
<font color="#FF6600">11111111</font>),
|
|
and the <font color="#FF6600">FirstRealGA</font> is maximizing (the default
|
|
action for EO is to maximize) the inverse of the sum (i.e. minimizing the
|
|
sum) of the square of its variables (also called the <font color="#FF6600">sphere
|
|
function</font>, whose solution is ... <font color="#FF6600">all zeroes</font>).
|
|
<p>And what you see on the screen when running one of these two programs
|
|
is, in each case, the initial and final population of an Evolutionary run,
|
|
one individual per line, its fitness first, then the number of items (bits
|
|
or real numbers) of the genotype, and the genotype itself. The final population
|
|
hopefully contains the solution in the discrete case, and is close to it
|
|
in the continuous case.
|
|
<br>
|
|
<hr WIDTH="100%"><a NAME="browse"></a><b><font color="#000099"><font size=+1>Browsing
|
|
the code:</font></font></b>
|
|
<p>Now you need to take a look at the program codes, either by browsing
|
|
alone through the sources for <a href="FirstBitGA.html">FirstBitGA</a>
|
|
and <a href="FirstRealGA.html">FirstRealGA</a>, or by following the guided
|
|
tour below. You might prefer to go directly to the <a href="#exercise1">exercises</a>.
|
|
<h3>
|
|
|
|
<hr WIDTH="100%"><a NAME="tour"></a><font color="#000099">Guided tour:</font></h3>
|
|
|
|
<ul>
|
|
<li>
|
|
<b><font color="#993300">General includes:</font></b><font color="#000000">Like
|
|
all C-like code, the file starts with include directives (<a href="FirstBitGA.html#start">Bit</a>
|
|
- <a href="FirstRealGA.html#start">Real</a>). Apart from standard includes,
|
|
the specific file to include is </font><b><font color="#FF6600">eo</font></b><font color="#000000">:
|
|
this is a file that contains the list of the all important representation-independent
|
|
EO files.</font></li>
|
|
|
|
<br>
|
|
<li>
|
|
<b><font color="#999900">Representation</font></b><font color="#000000">:
|
|
you then have to declare the type of individuals you will be handling.
|
|
All evolution-related objects you will need are templatized w.r.t. the
|
|
type of individuals.</font></li>
|
|
|
|
<ul>
|
|
<li>
|
|
<a href="FirstBitGA.html#representation">Bit</a> You first need to include
|
|
the representation-dependent file <b><tt><font color="#993300"><font size=+1>ga.h</font></font></tt></b>,
|
|
containing the bitstring representation and operators. More details about
|
|
<a href="eoRepresentation.html#bitstring">what is available for bitstrings
|
|
here</a>.<br>
|
|
You then say that you will be handling <b><font face="Arial,Helvetica"><a href="../../doc/html/classeo_bit.html">Bitstring
|
|
genotypes</a></font></b>, whose fitness is a double. This makes Indi derive
|
|
from the <a href="eoProgramming.html#STL">STL class</a> <font color="#993300">vector<bool></font></li>
|
|
|
|
<li>
|
|
<a href="FirstRealGA.html#representation">Real</a> You first need to include
|
|
the representation-dependent file <b><tt><font color="#993300"><font size=+1>es.h</font></font></tt></b>,
|
|
containing the bitstring representation and operators. More details about
|
|
<a href="eoRepresentation.html#real">what is available for real-values
|
|
here</a>.<br>
|
|
You then say that you will be handling <b><font face="Arial,Helvetica"><a href="../../doc/html/classeo_real.html">Real-valued
|
|
genotypes</a></font></b>, whose fitness is a double. This makes Indi derive
|
|
from the <a href="eoProgramming.html#STL">STL class</a> <font color="#993300">vector<double></font></li>
|
|
|
|
<br> </ul>
|
|
|
|
<li>
|
|
<b><font color="#CC0000">Fitness function:</font></b><font color="#000000">
|
|
the code for the fitness function is included in the file. It must take
|
|
as argument a reference to an individual (at the moment).</font></li>
|
|
|
|
<ul>
|
|
<li>
|
|
<a href="FirstBitGA.html#evalfunc">Bit</a> This function simply computes
|
|
the number of ones of the bitstring (it's called the OneMax function).
|
|
The optimum is of course the all-ones bitstring.</li>
|
|
|
|
<li>
|
|
<a href="FirstRealGA.html#evalfunc">Real</a> This function simply computes
|
|
the inverse of the sum of the squares of all variables (also called the
|
|
sphere function). The optimum is of course the all-zeroes vector.</li>
|
|
|
|
<br> </ul>
|
|
|
|
<li>
|
|
<a NAME="parametres"></a><b><font color="#3366FF">Parameters</font></b><font color="#000000">:
|
|
all parameters of the algorithm are declared here (<a href="FirstBitGA.html#parametres">Bit</a>
|
|
- <a href="FirstRealGA.html#parametres">Real</a>), and their values and
|
|
assigned. Of course, this means that you will need to recompile to change
|
|
these values - see Lesson 3 to get rid of that heavy requirement.</font></li>
|
|
|
|
<br>
|
|
<li>
|
|
<b><font color="#990000">Random seeding:</font></b><font color="#000000">
|
|
Random numbers play an important role in Evolutionary Algorithms. See in
|
|
<a href="eoProgramming.html#random">EO
|
|
programming hints</a> more details about how this is simulated in EO -
|
|
but as far as you are concerned now, remember that the </font><font color="#660000">global
|
|
Random Number Generator</font><font color="#000000"> is called </font><b><tt><font color="#660000"><font size=+1>rng</font></font></tt></b><font color="#000000">
|
|
and should be used everywhere you need a realization of a random variable
|
|
of known law. Moreover, this RNG requires a </font><b><tt><font color="#660000"><font size=+1>seed</font></font></tt></b><font color="#000000">,
|
|
which is set here (<a href="FirstBitGA.html#random">Bit</a> - <a href="FirstRealGA.html#random">Real</a>):
|
|
every time you run the algorithm with the </font><font color="#FF6600">same
|
|
seed</font><font color="#000000">, you will get the </font><font color="#FF6600">same
|
|
result</font><font color="#000000">. Hence, to test the robustness of your
|
|
algorithm, you should run it with different seeds. This is rather time
|
|
consuming in the present programs, so we suggest that you wait until Lesson
|
|
3 to do so.</font></li>
|
|
|
|
<br>
|
|
<li>
|
|
<b><font color="#CC0000">Fitness function encapsulation: </font></b><font color="#000000">EO
|
|
is based on the notion of <a href="eoProgramming.html#functors">functors</a>
|
|
- hence you now need to encapsulate your fitness function into a functor
|
|
object. This is what is done here (<a href="FirstBitGA.html#eval">Bit</a>
|
|
- <a href="FirstRealGA.html#eval">Real</a>).</font></li>
|
|
|
|
<br>
|
|
<li>
|
|
<b><font color="#CC33CC">Initialization</font></b><font color="#000000">:
|
|
to initialize the population, first declare an empty object of class </font><b><tt><font color="#990000">eoPop<Indi></font></tt></b><font color="#000000">,
|
|
which is basically an <a href="eoProgramming.html#STL">STL</a> </font><b><tt><font color="#990000">vector<Indi></font></tt></b><font color="#000000">,
|
|
then fill it with Indi's.</font> And remember that
|
|
<b><tt><font color="#990000">v.push_back</font></tt></b>
|
|
simply appends its argument at the end of <a href="eoProgramming.html#STL">STL</a>
|
|
vector <b><tt><font color="#993300">v.</font></tt></b></li>
|
|
|
|
<ul>
|
|
<li>
|
|
<a href="FirstBitGA.html#init">Bit</a> <b><tt><font color="#990000">rng.flip()</font></tt></b>
|
|
return a <font face="Arial,Helvetica"><font size=+1><a href="../../doc/html/classeo_rng.html">random
|
|
boolean</a></font></font></li>
|
|
|
|
<li>
|
|
<a href="FirstRealGA.html#init">Real</a> <b><tt><font color="#990000">rng.uniform()</font></tt></b>
|
|
returns a <font face="Arial,Helvetica"><font size=+1><a href="../../doc/html/classeo_rng.html">real
|
|
value uniformly drawn in [0,1].</a></font></font></li>
|
|
|
|
<br> </ul>
|
|
|
|
<li>
|
|
<b><font color="#3366FF">Output</font></b><font color="#000000">: take
|
|
a snapshot at the initial population (<a href="FirstBitGA.html#output">Bit</a>
|
|
- <a href="FirstRealGA.html#output">Real</a>). Sort it first, so the best
|
|
individuals are first, and display it. Note that an eoPop has a </font><b><tt><font color="#990000"><<</font></tt></b><font color="#000000">
|
|
method, which means that a simple </font><b><tt><font color="#990000">os
|
|
<< pop </font></tt></b><font color="#000000">streams the </font><b><tt><font color="#990000">pop</font></tt></b><font color="#000000">
|
|
onto the ostream </font><b><tt><font color="#990000">os</font></tt></b><font color="#000000">.
|
|
This is true for </font><font color="#FF6600">all objects of of class </font><font color="#000000"><b><font face="Arial,Helvetica"><font size=+1><a href="../../doc/html/classeo_printable.html">eoPrintable</a></font></font></b>
|
|
(most EO objects) through the method </font><b><tt><font color="#990000">printOn</font></tt></b><font color="#000000">
|
|
(which is then called by the </font><b><tt><font color="#990000"><<</font></tt></b><font color="#000000">
|
|
operator).</font></li>
|
|
|
|
<br>
|
|
<li>
|
|
<b><font color="#009900">Evolution engine:</font></b><font color="#000000">
|
|
The selection/replacement mechanism (<a href="FirstBitGA.html#engine">Bit</a>
|
|
- <a href="FirstRealGA.html#engine">Real</a>) is a simple generational
|
|
GA here: a simple selector, and a generational replacement. The <b><font face="Arial,Helvetica"><font size=+1><a href="../../doc/html/classeo_det_tournament_select.html">eoDetTournamentSelect</a></font></font></b>
|
|
has been chosen as a robust selection, and the generational replacement
|
|
(all parents are replaced by the offspring) is hard-coded in the eoSGA
|
|
<a href="#algorithm">algorithm</a>.</font></li>
|
|
|
|
<br>
|
|
<li>
|
|
<font color="#CC33CC"><b>Variation operators</b>:</font><font color="#000000">
|
|
in the simple algorithm considered here, individuals undergo </font><font color="#CC33CC">crossover</font><font color="#000000">
|
|
and </font><font color="#CC33CC">mutation</font><font color="#000000">.
|
|
In EO, these operators are (<a href="eoProgramming.html#functors">functor</a>)
|
|
objects of class</font> <b><font face="Arial,Helvetica"><font size=+1><a href="../../doc/html/classeo_quad_op.html">eoQuadOp</a></font></font></b>
|
|
(binary operator that modifies both its arguments) and <b><font face="Arial,Helvetica"><font size=+1><a href="../../doc/html/classeo_mon_op.html">eoMonOp</a></font></font></b>
|
|
(unary operator). These operators are applied in turn to all selected
|
|
parents, according to user-defined probabilities. These probabilities
|
|
are defined with all other <a href="#parametres">parameters</a>, and will
|
|
be passed to the <b><tt><font color="#FF6666"><font size=+1>eoSGA </font></font></tt></b><a href="#parametres">algorithm</a><font color="#000000">.
|
|
For more details on these classes, go to the <a href="eoOperators.html#crossover">algorithm-based
|
|
corresponding pages</a>, or to their respective documentation pages.</font></li>
|
|
|
|
<br>
|
|
<ul>
|
|
<li>
|
|
<a href="FirstBitGA.html#operators">Bit</a> The crossover <b><font face="Arial,Helvetica"><font size=+1><a href="../../doc/html/classeo1_pt_bit_crossover.html">eo1PtBitXover</a></font></font></b>
|
|
is the standard <font color="#CC33CC">1-point crossover</font>, and <b><font face="Arial,Helvetica"><font size=+1><a href="../../doc/html/classeo_bit_mutation.html">eoBitMutation</a></font></font></b>
|
|
is the standard <font color="#FF6600">bit-flip mutation</font> that randomly
|
|
flips all bits with a given probability <b><tt>P_MUT_PER_BIT.</tt></b></li>
|
|
|
|
<br><b><font color="#FF0000">Warning</font></b>: the <b><tt>P_MUT_PER_BIT</tt></b>
|
|
probability is an <font color="#FF6600">internal parameter</font> of the
|
|
<b><tt><font color="#CC33CC"><font size=+1>eoBinMutation</font></font></tt></b>,
|
|
it is <b><font color="#FF6600">NOT</font></b> the probability of mutation
|
|
at the individual level. EO corrects what can be viewed as an inconsistency
|
|
in Holland's original work, further used in Goldberg's book by separating
|
|
the probability of mutation for each individual (independent of the type
|
|
of mutation that will be applied) from the probability of flipping each
|
|
bit, which is specific of the bit-flip mutation. Hence, to run the
|
|
same algorithm as Goldberg's SGA, the mutation probability (at individual
|
|
level) is 1, and the probability of flipping each bit is <b><tt>P_MUT_PER_BIT.</tt></b>
|
|
<li>
|
|
<a href="FirstRealGA.html#operators">Real</a> The crossover <b><font face="Arial,Helvetica"><font size=+1><a href="../../doc/html/classeo_segment_crossover.html">eoSegmentCrossover</a></font></font></b>
|
|
is the standard <font color="#CC33CC">segment crossover</font> for real-valued
|
|
vectors, that chooses a point randomly on the segment between both parents
|
|
(also termed <font color="#CC33CC">BLX-0</font>). <b><font face="Arial,Helvetica"><font size=+1><a href="../../doc/html/classeo_uniform_mutation.html">eoUniformMutation</a></font></font></b>
|
|
is the <font color="#CC33CC">uniform mutation</font> for real-valued vectors
|
|
that chooses a new value for each variable uniformly on an interval centered
|
|
on the parent value. The width of the interval is an <font color="#FF6600">internal
|
|
parameter</font> of the object, here called <b><tt>EPSILON</tt></b>.</li>
|
|
|
|
<br> </ul>
|
|
|
|
<li>
|
|
<b><font color="#3366FF">Stopping criterion:</font></b><font color="#000000">
|
|
Specify a </font><font color="#3366FF">maximum number of generations</font><font color="#000000">
|
|
to run (<a href="FirstBitGA.html#stop">Bit</a> - <a href="FirstRealGA.html#stop">Real</a>):
|
|
the simplest of all stopping criteria at the moment, using an object of
|
|
a sub-class of class </font><b><font face="Arial,Helvetica"><font color="#3366FF"><font size=+1><a href="../../doc/html/classeo_continue.html">eoContinue</a></font></font></font></b><font color="#000000">.</font></li>
|
|
|
|
<br>
|
|
<li>
|
|
<a NAME="algorithm"></a><b><font color="#FF6666">The algorithm: </font></b><font color="#000000">the
|
|
simple algorithm that is used here, called </font><b><tt><font color="#FF6666"><font size=+1>eoSGA
|
|
</font></font></tt></b><font color="#000000">requires
|
|
as parameters a </font><font color="#FF6600">selector</font><font color="#000000">,
|
|
a </font><font color="#FF6600">crossover</font><font color="#000000"> and
|
|
the associated </font><font color="#FF6600">crossover rate</font><font color="#000000">,
|
|
a </font><font color="#FF6600">mutation</font><font color="#000000"> and
|
|
the associated </font><font color="#FF6600">mutation rate,</font><font color="#000000">
|
|
and a </font><font color="#FF6600">stopping criterion</font><font color="#000000">.
|
|
Take a look at the corresponding
|
|
<a href="eoSGA.html#constructor">constructor</a>
|
|
of the class </font><b><tt><font color="#FF6666"><font size=+1>eoSGA</font></font></tt></b><font color="#000000">:
|
|
it only initializes its <a href="eoSGA.html#parametres">private data</a>
|
|
with the parameters. Now look at the <a href="eoSGA.html#generation">operator()</a>
|
|
method - the one that is called in the code for <a href="FirstBitGA.html#generation">FirstBitGA</a>
|
|
or <a href="FirstRealGA.html#generation">FirstRealGA</a> - and you'll find
|
|
out that is is as simple as it sounds.</font></li>
|
|
|
|
<br>
|
|
<li>
|
|
<b><font color="#3366FF">Output</font></b><font color="#000000">: After
|
|
running the algorithm, output the sorted final population (<a href="FirstBitGA.html#final_output">Bit</a>
|
|
- <a href="FirstRealGA.html#final_output">Real</a>) - and look at the best
|
|
individual: this is the result of the algorithm.</font></li>
|
|
|
|
<br>
|
|
<li>
|
|
<b><font color="#990000">Main body:</font></b><font color="#000000"> for
|
|
technical reasons (intercepting the exceptions), we need a main like this
|
|
one (<a href="FirstBitGA.html#main">Bit</a> - <a href="FirstRealGA.html#main">Real</a>).,
|
|
and you should not touch it unless you know what you are doing. Simply
|
|
note that this main calls the function main_function, which we have been
|
|
discussing up to now!</font></li>
|
|
</ul>
|
|
|
|
<h3>
|
|
|
|
<hr WIDTH="100%"><a NAME="exercise1"></a><font color="#000099">Exercise
|
|
1: maximize your own function</font></h3>
|
|
This is very easy - if your search space is that of bitstring or of unbounded
|
|
real numbers.
|
|
<ul>
|
|
<li>
|
|
Go to the tutorial directory, and <font color="#FF6600">copy</font> the
|
|
program you want to modify onto <b><tt><font color="#663300">mytest.cpp.</font></tt></b></li>
|
|
|
|
<li>
|
|
<font color="#FF6600">Edit</font> <b><tt><font color="#990000">mytest.cpp</font></tt></b>
|
|
with any text editor:</li>
|
|
|
|
<li>
|
|
<font color="#FF6600">Modify</font> the fitness function itself (<a href="FirstBitGA.html#evalfunc">binary_value</a>
|
|
in <font color="#FF6666"><b><tt>FirstBitGA</tt></b><font face="Courier New,Courier">,</font></font><a href="FirstRealGA.html#evalfunc">real_value</a>
|
|
in <font color="#FF6666"><b><tt>FirstRealGA</tt></b><font face="Courier New,Courier">)</font></font></li>
|
|
|
|
<li>
|
|
<font color="#FF6600">Compile</font> the program by typing <b><tt><font color="#990000">make
|
|
mytest</font></tt></b> at system prompt</li>
|
|
|
|
<li>
|
|
<font color="#FF6600">Run</font> the new program by entering the command
|
|
<b><tt><font color="#990000">mytest</font></tt></b>
|
|
at system prompt.</li>
|
|
</ul>
|
|
|
|
<h3>
|
|
|
|
<hr WIDTH="100%"><a NAME="exercise2"></a><font color="#000099">Exercise
|
|
2: check the differences between both programs</font></h3>
|
|
Go and take a look at the code for these programs <font color="#000000">(<a href="FirstBitGA.html">Bit</a>
|
|
- <a href="FirstRealGA.html">Real</a>)</font>. Use the symbolic representation
|
|
of an Evolutionary Algorithm (you should understand that figure now, otherwise
|
|
go <a href="eoIntro.html">there</a> and come back) to understand how each
|
|
part of the EA is coded. Try to spot the differences between both codes:
|
|
there are not so many!
|
|
<br>After you've tried that alone, take a look at the <a href="Firstmerge.html">solution</a>
|
|
:-)
|
|
<h3>
|
|
|
|
<hr WIDTH="100%"><a NAME="exercise3"></a><font color="#000099">Exercise
|
|
3: change the selection procedure</font></h3>
|
|
This is rather straightforward ... if you know what other types of selection
|
|
are available!
|
|
<br>At the moment, let's only consider only the following simple ones:
|
|
<ul>
|
|
<li>
|
|
You already know the <font color="#FF6600">tournament selection</font></li>
|
|
|
|
<br><font color="#FF0000">Syntax: </font><tt><font color="#009900"><b>eoDetTournamentSelect<Indi>
|
|
select(T_SIZE); </b>// T_SIZE in [2,POP_SIZE)</font></tt>
|
|
<li>
|
|
Try the well-known <font color="#FF6600">roulette wheel</font></li>
|
|
|
|
<br> <font color="#FF0000">Syntax: </font> <b><tt><font color="#009900">eoProportionalSelect<Indi>
|
|
select;</font></tt></b>
|
|
<li>
|
|
Or the <font color="#FF6600">stochastic binary tournament</font></li>
|
|
|
|
<br><font color="#FF0000">Syntax: </font><b><tt><font color="#009900">eoStochTournamentSelect<Indi>
|
|
select(RATE); </font></tt></b><tt><font color="#009900">
|
|
// RATE in ]0.5,1]</font></tt>
|
|
<li>
|
|
and of course the <font color="#FF6600">random</font> selection should
|
|
give bad results!</li>
|
|
|
|
<br><font color="#FF0000">Syntax: </font><b><tt><font color="#009900">eoRandomSelect<Indi>
|
|
select;</font></tt></b></ul>
|
|
Note that all these classes of eoObjects are derived from the abstract
|
|
class
|
|
<b><font face="Arial,Helvetica"><font size=+1><a href="../../doc/html/classeo_select_one.html">eoSelectOne.</a></font></font></b>
|
|
To find out exactly how each procedure selects the individuals, read the
|
|
corresponding <a href="eoEngine.html#selection">component-based page</a>.
|
|
<p>
|
|
<hr WIDTH="100%"><b><font color="#000099"><font size=+2>Lessons learned:</font></font></b>
|
|
<ul>
|
|
<li>
|
|
in EO, all actions are performed by <a href="eoProgramming.html#functors">functor
|
|
objects</a> (this section is the last time in this tutorial that there
|
|
is a direct link to the <a href="eoProgramming.html">EO Programming hints</a>
|
|
page - though the link at top and bottom of all pages will remain there).</li>
|
|
|
|
<li>
|
|
in EO, all object you will usually need to manipulate are <a href="eoProgramming.html#templates">templatized</a><b><font color="#FF6600">
|
|
w.r.t. the type of the individual</font></b> you are handling.</li>
|
|
|
|
<li>
|
|
The type of the individual is itself <a href="eoProgramming.html#templates">templatized</a><b><font color="#FF6600">
|
|
w.r.t. the type of fitness</font></b> (double by default).</li>
|
|
|
|
<li>
|
|
In EO (actually, in EC!) <font color="#CC33CC">initialization and variation</font>
|
|
operators are <font color="#999900">representation</font>-dependent, while
|
|
the <font color="#009900">evolution engine</font> is <font color="#999900">representation</font>-independent
|
|
(well, like any rule, this one does have some exceptions).</li>
|
|
|
|
<li>
|
|
Changing the <font color="#990000">fitness function</font>, or the <font color="#009900">selection
|
|
procedure</font> inside the generational GA evolution engine is straightforward.</li>
|
|
|
|
<li>
|
|
remember, all <font color="#FF6600">solutions</font> to exercises are in
|
|
the same sub-dir of dir Tutorial than the lesson itself (see <a href="NoWay.html">here</a>).</li>
|
|
</ul>
|
|
|
|
<hr WIDTH="100%"><a href="eoLesson2.html">Lesson 2</a> -
|
|
<a href="eoTutorial.html">Tutorial
|
|
main page</a> -
|
|
<a href="eoTopDown.html">Algorithm-Based</a> - <a href="eoBottomUp.html">Component-Based</a>
|
|
- <a href="eoProgramming.html">Programming hints</a> - <font face="Arial,Helvetica"><font size=+1><a href="../../doc/html/index.html">EO
|
|
documentation</a></font></font>
|
|
<br>
|
|
<hr>
|
|
<address>
|
|
<a href="mailto:Marc.Schoenauer@inria.fr">Marc Schoenauer</a></address>
|
|
|
|
<br><!-- Created: Fri Nov 3 18:49:12 CET 2000 --><!-- hhmts start -->Last
|
|
modified: Fri Nov 3 18:49:12 CET 2000<!-- hhmts end -->
|
|
</body>
|
|
</html>
|