是想用matlab求解一个多变量(3个)有约束非线性规划问题,目标函数已经给出了,但是约束条件如果直接写的话太复杂了,所以事先写了一个m文件function [Kc,P_max,P_min,Bn,Jc,Jp,C]=Sluice_first(x),Kc,Bn,Jc,P_max,都相当于是x1,x2,x3的函数。想直接在此引用过来。但是报错为“未定义函数或变量x”。望各位解答,不胜感激!具体代码如下所示:
clear;close;clc
%% 约束条件和目标函数构建
[Kc,P_max,P_min,Bn,Jc,Jp,C] = Sluice_first(x);
fun = @(x) x(1)*x(2)+(0.5+0.5+x(3))*x(3);
bind1 = @(x) Kc>1.25;
bind2 =@(x) P_max<1.2*85000;
bind3 =@(x) Bn<2.5;
bind4 =@(x) Jc<0.6;
%% 初始化
popsize = 500; % 粒子个数
dim = 3; % 维度
max_iter = 100; % 最大迭代次数
xlimit_max = [28.8 2 1.5]'; % 由等式约束推出位置边界
xlimit_min = [18 0.7 0.5];
vlimit_max = xlimit_max+0.5;
vlimit_min = vlimit_max;
w = 0.6; % 惯性权重
c1 = 0.5;c2 = 1.5;
pr = 0.4; % 变异率
pop_x = zeros(dim,popsize); % 当前粒子位置
pop_v = zeros(dim,popsize); % 当前粒子速度
fitness_pop = zeros(1,popsize); % 粒子群当前位置适应度函数
fitness_lbest = zeros(1,popsize); % 个体粒子的历史最优极值
rand('state',sum(clock));
for j = 1:popsize
% 位置初始化
pop_x(1,j) = xlimit_min(1) + rand*(xlimit_max(1) - xlimit_min(1));
pop_x(2,j) = sqrt(2-pop_x(1,j));
pop_x(3,j) = sqrt((3 - pop_x(2,j))/2);
% 速度初始化
for i = 1:dim
pop_v(i,j) = vlimit_min(i) + rand*(vlimit_max(i) - vlimit_min(i));
end
end
%% 初始化个体极值
lbest = pop_x; % 个体历史最佳极值记录
for j =1: popsize
if bind1(pop_x(:,j))
if bind2(pop_x(:,j))
fitness_lbest(j) = fun(pop_x(:,j));
else fitness_lbest(j) = 500;
end
else fitness_lbest(j) = 500;
end
end
%% 初始化全局极值
popbest = pop_x(:,1);
fitness_popbest = fitness_lbest(1);
for j = 2:popsize
if fitness_lbest(j) < fitness_popbest
fitness_popbest = fitness_lbest(j);
popbest = pop_x(:,j);
end
end
tic
%% 粒子群迭代
iter = 1; % 当前迭代次数
record = zeros(max_iter,1); % 记录每次迭代的全局极小值
format long;
while iter <= max_iter
for j = 1:popsize
% 更新速度 边界处理
pop_v(:,j) = w*pop_v(:,j) + c1*rand*(lbest(:,j) - pop_x(:,j)) +...
c2*rand*(popbest - pop_x(:,j));
for i = 1:dim
if pop_v(i,j) > vlimit_max(i)
pop_v(i,j) = vlimit_max(i);
elseif pop_v(i,j) < vlimit_min(i)
pop_v(i,j) = vlimit_min(i);
end
end
% 更新位置 边界处理 修正位置 (等式约束)
pop_x(:,j) = pop_x(:,j) + pop_v(:,j);
for i = 1:dim
if pop_x(i,j) > xlimit_max(i)
pop_x(i,j) = xlimit_max(i);
elseif pop_x(i,j) < xlimit_min(i)
pop_x(i,j) = xlimit_min(i);
end
end
% 进行自适应变异
if rand < pr
i = ceil(dim*rand);
pop_x(i,j) = xlimit_min(i) + rand*(xlimit_max(i) - xlimit_min(i));
end
% 约束条件限制 类似罚函数法
if bind1(pop_x(:,j))
if bind2(pop_x(:,j))
if bind3(pop_x(:,j))
if bind4(pop_x(:,j))
fitness_pop(j) = fun(pop_x(:,j));
else fitness_pop(j) = 500;
end
else fitness_pop(j) = 500;
end
else fitness_pop(j) = 500;
end
else fitness_pop(j) = 500;
end
% 当前适应度与个体历史最佳适应度作比较
if fitness_pop(j) < fitness_lbest(j)
lbest(:,j) = pop_x(:,j);
fitness_lbest(j) = fitness_pop(j);
end
% 个体历史最佳适应度与种群历史最佳适应度作比较
if fitness_popbest > fitness_lbest(j)
fitness_popbest = fitness_lbest(j);
popbest = lbest(:,j);
end
end
record(iter) = fitness_popbest;
iter = iter + 1;
end
toc
%% 输出解
minx = popbest
miny = fitness_popbest
plot(record,'r-');
title('粒子群算法迭代过程');
xlabel('迭代次数');
ylabel('当前迭代最佳函数值');
你好,我是有问必答小助手,非常抱歉,本次您提出的有问必答问题,技术专家团超时未为您做出解答
本次提问扣除的有问必答次数,将会以问答VIP体验卡(1次有问必答机会、商城购买实体图书享受95折优惠)的形式为您补发到账户。
因为有问必答VIP体验卡有效期仅有1天,您在需要使用的时候【私信】联系我,我会为您补发。