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鸡群算法。。。。。- % -------------------------------------------------------------------------
- % Chicken Swarm Optimization (CSO) (demo)
- % Programmed by Xian-Bing Meng
- % Updated at Jun 21, 2015.
- % Email: x.b.meng12@gmail.com
- %
- % This is a simple demo version only implemented the basic idea of CSO for
- % solving the unconstrained problem, namely Sphere function.
- % The details about CSO are illustratred in the following paper.
- % Xian-Bing Meng, et al. A new bio-inspired algorithm: Chicken Swarm
- % Optimization. The Fifth International Conference on Swarm Intelligence
- %
- % The parameters in CSO are presented as follows.
- % FitFunc % The objective function
- % M % Maxmimal generations (iterations)
- % pop % Population size
- % dim % Dimension
- % G % How often the chicken swarm can be updated.
- % rPercent % The population size of roosters accounts for "rPercent"
- % percent of the total population size
- % hPercent % The population size of hens accounts for "hPercent" percent
- % of the total population size
- % mPercent % The population size of mother hens accounts for "mPercent"
- % percent of the population size of hens
- %
- % Using the default value,CSO can be executed using the following code.
- % [ bestX, fMin ] = CSO
- % -------------------------------------------------------------------------
-
- %*************************************************************************
- % Revision 1
- % Revised at May 23, 2015
- % 1.Note that the previous version of CSO doen't consider the situation
- % that there maybe not exist hens in a group.
- % We assume there exist at least one hen in each group.
- % Revision 2
- % Revised at Jun 24, 2015
- % 1.Correct an error at line "100".
- %*************************************************************************
- % Main programs
- function [ bestX, fMin ] = CSO( FitFunc, M, pop, dim, G, rPercent, hPercent, mPercent )
- % Display help
- help CSO.m
- %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
- % set the default parameters
- if nargin < 1
- FitFunc = @Sphere;
- M = 1000;
- pop = 100;
- dim = 20;
- G = 10;
- rPercent = 0.15;
- hPercent = 0.7;
- mPercent = 0.5;
- end
- rNum = round( pop * rPercent ); % The population size of roosters
- hNum = round( pop * hPercent ); % The population size of hens
- cNum = pop - rNum - hNum; % The population size of chicks
- mNum = round( hNum * mPercent ); % The population size of mother hens
- lb= -100*ones( 1,dim ); % Lower bounds
- ub= 100*ones( 1,dim ); % Upper bounds
- %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
- %Initialization
- for i = 1 : pop
- x( i, : ) = lb + (ub - lb) .* rand( 1, dim );
- fit( i ) = FitFunc( x( i, : ) );
- end
- pFit = fit; % The individual's best fitness value
- pX = x; % The individual's best position corresponding to the pFit
- [ fMin, bestIndex ] = min( fit ); % fMin denotes the global optimum
- % bestX denotes the position corresponding to fMin
- bestX = x( bestIndex, : );
- %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
- % Start the iteration.
-
- for t = 1 : M
-
- % This parameter is to describe how closely the chicks would follow
- % their mother to forage for food. In fact, there exist cNum chicks,
- % thus only cNum values of FL would be used.
- FL = rand( pop, 1 ) .* 0.4 + 0.5;
-
- % The chicken swarm'status about hierarchal order, dominance
- % relationship, mother-child relationship, the roosters, hens and the
- % chicks in a group will remain stable during a period of time. These
- % statuses can be updated every several (G) time steps.The parameter G
- % is used to simulate the situation that the chicken swarm have been
- % changed, including some chickens have died, or the chicks have grown
- % up and became roosters or hens, some mother hens have hatched new
- % offspring (chicks) and so on.
-
- if mod( t, G ) == 1 || t == 1
-
- [ ans, sortIndex ] = sort( pFit );
- % How the chicken swarm can be divided into groups and the identity
- % of the chickens (roosters, hens and chicks) can be determined all
- % depend on the fitness values of the chickens themselves. Hence we
- % use sortIndex(i) to describe the chicken, not the index i itself.
-
- motherLib = randperm( hNum, mNum ) + rNum;
- % Randomly select mNum hens which would be the mother hens.
- % We assume that all roosters are stronger than the hens, likewise,
- % hens are stronger than the chicks.In CSO, the strong is reflected
- % by the good fitness value. Here, the optimization problems is
- % minimal ones, thus the more strong ones correspond to the ones
- % with lower fitness values.
-
- % Given the fact the 1 : rNum chickens' fitness values maybe not
- % the best rNum ones. Thus we use sortIndex( 1 : rNum ) to describe
- % the roosters. In turn, sortIndex( (rNum + 1) :(rNum + 1 + hNum ))
- % to describle the mother hens, .....chicks.
- % Here motherLib include all the mother hens.
-
- %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
- % Randomly select each hen's mate, rooster. Hence we can determine
- % which group each hen inhabits using "mate".Each rooster stands
- % for a group.For simplicity, we assume that there exist only one
- % rooster and at least one hen in each group.
- mate = randpermF( rNum, hNum );
-
- % Randomly select cNum chicks' mother hens
- mother = motherLib( randi( mNum, cNum, 1 ) );
- end
-
- %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
- for i = 1 : rNum % Update the rNum roosters' values.
-
- % randomly select another rooster different from the i (th) one.
- anotherRooster = randiTabu( 1, rNum, i, 1 );
- if( pFit( sortIndex( i ) ) <= pFit( sortIndex( anotherRooster ) ) )
- tempSigma = 1;
- else
- tempSigma = exp( ( pFit( sortIndex( anotherRooster ) ) - ...
- pFit( sortIndex( i ) ) ) / ( abs( pFit( sortIndex(i) ) )...
- + realmin ) );
- end
-
- x( sortIndex( i ), : ) = pX( sortIndex( i ), : ) .* ( 1 + ...
- tempSigma .* randn( 1, dim ) );
- x( sortIndex( i ), : ) = Bounds( x( sortIndex( i ), : ), lb, ub );
- fit( sortIndex( i ) ) = FitFunc( x( sortIndex( i ), : ) );
- end
-
- for i = ( rNum + 1 ) : ( rNum + hNum ) % Update the hNum hens' values.
-
- other = randiTabu( 1, i, mate( i - rNum ), 1 );
- % randomly select another chicken different from the i (th)
- % chicken's mate. Note that the "other" chicken's fitness value
- % should be superior to that of the i (th) chicken. This means the
- % i (th) chicken may steal the better food found by the "other"
- % (th) chicken.
-
- c1 = exp( ( pFit( sortIndex( i ) ) - pFit( sortIndex( mate( i - ...
- rNum ) ) ) )/ ( abs( pFit( sortIndex(i) ) ) + realmin ) );
-
- c2 = exp( ( -pFit( sortIndex( i ) ) + pFit( sortIndex( other ) )));
- x( sortIndex( i ), : ) = pX( sortIndex( i ), : ) + ( pX(...
- sortIndex( mate( i - rNum ) ), : )- pX( sortIndex( i ), : ) )...
- .* c1 .* rand( 1, dim ) + ( pX( sortIndex( other ), : ) - ...
- pX( sortIndex( i ), : ) ) .* c2 .* rand( 1, dim );
- x( sortIndex( i ), : ) = Bounds( x( sortIndex( i ), : ), lb, ub );
- fit( sortIndex( i ) ) = FitFunc( x( sortIndex( i ), : ) );
- end
-
- for i = ( rNum + hNum + 1 ) : pop % Update the cNum chicks' values.
- x( sortIndex( i ), : ) = pX( sortIndex( i ), : ) + ( pX( ...
- sortIndex( mother( i - rNum - hNum ) ), : ) - ...
- pX( sortIndex( i ), : ) ) .* FL( i );
- x( sortIndex( i ), : ) = Bounds( x( sortIndex( i ), : ), lb, ub );
- fit( sortIndex( i ) ) = FitFunc( x( sortIndex( i ), : ) );
- end
-
- %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
- % Update the individual's best fitness vlaue and the global best one
-
- for i = 1 : pop
- if ( fit( i ) < pFit( i ) )
- pFit( i ) = fit( i );
- pX( i, : ) = x( i, : );
- end
-
- if( pFit( i ) < fMin )
- fMin = pFit( i );
- bestX = pX( i, : );
- end
- end
- end
- % End of the main program
- %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
- % The following functions are associated with the main program
- %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
- % This function is the objective function
- function y = Sphere( x )
- y = sum( x .^ 2 );
- % Application of simple limits/bounds
- function s = Bounds( s, Lb, Ub)
- % Apply the lower bound vector
- temp = s;
- I = temp < Lb;
- temp(I) = Lb(I);
-
- % Apply the upper bound vector
- J = temp > Ub;
- temp(J) = Ub(J);
- % Update this new move
- s = temp;
- %--------------------------------------------------------------------------
- % This function generate "dim" values, all of which are different from
- % the value of "tabu"
- function value = randiTabu( min, max, tabu, dim )
- value = ones( dim, 1 ) .* max .* 2;
- num = 1;
- while ( num <= dim )
- temp = randi( [min, max], 1, 1 );
- if( length( find( value ~= temp ) ) == dim && temp ~= tabu )
- value( num ) = temp;
- num = num + 1;
- end
- end
- %--------------------------------------------------------------------------
- function result = randpermF( range, dim )
- % The original function "randperm" in Matlab is only confined to the
- % situation that dimension is no bigger than dim. This function is
- % applied to solve that situation.
- temp = randperm( range, range );
- temp2 = randi( range, dim, 1 );
- index = randperm( dim, ( dim - range ) );
- result = [ temp, temp2( index )' ];
复制代码 代码下载:https://pan.baidu.com/s/18So1iW4q2ifcMruSuksqEg
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