www.gusucode.com > matlab编程遗传算法计算匹配电路源码程序 > code1/code/MATLAB源代码/genetic/Test_fns/objgold.m
% OBJGOLD.M (OBJective function for GOLDstein-price function) % % This function implements the GOLDSTEIN-PRICE function. % % Syntax: ObjVal = objgold(Chrom,rtn_type) % % Input parameters: % Chrom - Matrix containing the chromosomes of the current % population. Each row corresponds to one individual's % string representation. % if Chrom == [], then special values will be returned % rtn_type - if Chrom == [] and % rtn_type == 1 (or []) return boundaries % rtn_type == 2 return title % rtn_type == 3 return value of global minimum % % Output parameters: % ObjVal - Column vector containing the objective values of the % individuals in the current population. % if called with Chrom == [], then ObjVal contains % rtn_type == 1, matrix with the boundaries of the function % rtn_type == 2, text for the title of the graphic output % rtn_type == 3, value of global minimum % % % Author: Hartmut Pohlheim % History: 25.11.93 file created % 27.11.93 text of title and rtn_type added % 16.12.93 rtn_type == 3, return value of global minimum % 01.03.94 name changed in obj* % 14.01.03 updated for MATLAB v6 by Alex Shenfield function ObjVal = objgold(Chrom,rtn_type); % 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 rtn_type == 2 ObjVal = 'GOLDSTEIN-PRICE function'; % return value of global minimum elseif rtn_type == 3 ObjVal = 3; % define size of boundary-matrix and values else brd = 3; % x1 x2 ObjVal = [-brd -brd; % lower bounds brd brd]; % upper bounds end % if two variables, compute values of function elseif Nvar == 2 % GOLDSTEIN-PRICE function % -2 <= x1 <= 2 ; -2 <= x2 <= 2 (or -10 <= xi <= 10) % global minimum at (x1,x2)=(0,-1) ; fmin=3 x1 = Chrom(:,1); x2 = Chrom(:,2); ObjVal = ((1+(x1+x2+1).^2.*(19-14*x1+3*x1.^2-14*x2+6*x1.*x2+3*x2.^2))... .*(30+(2*x1-3*x2).^2.*(18-32*x1+12*x1.^2+48*x2-36*x1.*x2+27*x2.^2))); % otherwise error, wrong format of Chrom else error('size of matrix Chrom is not correct for function evaluation'); end % End of function