% OBJFUN2.M      (OBJective function for rosenbrock's FUNction)%% This function implements the ROSENBROCK valley (DE JONG's Function 2).%% Syntax:  ObjVal = objfun2(Chrom,switch_)%% Input parameters:%    Chrom     - Matrix containing the chromosomes of the current%                population. Each row corresponds to one%                individual's string representation.%                if called with Chrom == [], then boundaries of%                the function or title for figure will be returned%    switch_    - if Chrom == [] and switch_ == 1 (or []) then return%                boundaries, if switch_ == 2 return title%% Output parameters:%    ObjVal    - Column vector containing the objective values of the%                individuals in the current population.%                if called with Chrom == [], then ObjVal contains%                the matrix with the boundaries of the function or%                the Text for the title of the graphic output%                % Author:     Hartmut Pohlheim% History:    26.01.94     file created%             01.03.94     name changed in obj*function ObjVal = objfun2(Chrom,switch_);% Dimension of objective function   Dim = 2;   % Compute population parameters   [Nind,Nvar] = size(Chrom);% Check size of Chrom and do the appropriate thing   % if Chrom is [], then define size of boundary-matrix and values   if Nind == 0      % return text of title for graphic output      if switch_ == 2         ObjVal = ['ROSENBROCKs function 2-' int2str(Dim)];      % return value of global minimum      elseif switch_ == 3         ObjVal = 0;      % define size of boundary-matrix and values      else            % lower and upper bound, identical for all n variables                 ObjVal = [-2; 2];         ObjVal = ObjVal(1:2,ones(Dim,1));      end   % if Dim variables, compute values of function   elseif Nvar == Dim      % function 11, sum of 100* (x(i+1) -xi^2)^2+(1-xi)^2 for i = 1:Dim (Dim=10)      % n = Dim, -10 <= xi <= 10      % global minimum at (xi)=(1) ; fmin=0      Mat1 = Chrom(:,1:Nvar-1);      Mat2 = Chrom(:,2:Nvar);      if Dim == 2         ObjVal = 100*(Mat2-Mat1.^2).^2+(1-Mat1).^2;      else         ObjVal = sum((100*(Mat2-Mat1.^2).^2+(1-Mat1).^2)')';      end      % otherwise error, wrong format of Chrom   else      error('size of matrix Chrom is not correct for function evaluation');   end   % End of function