1 clc, clear
 2 %%%求解线性规划
 3 %%min(x) c'x,c、x为n维列向量
 4 %%s.t. {Ax <= b; Aeq * x = beq; lb <= x <= ub}
 5 %max z = 2x1 + 3x2 - 5x3;
 6 %{x1 + x2 + x3 = 7; 2x1 - 5x2 + x3 >= 10; x1 + 3x2 + x3 <= 12; x1, x2, x3 >= 0}
 7 % c = [2; 3; -5];
 8 % a = [-2, 5, -1; 1, 3, 1];
 9 % b = [-10; 12];
10 % aeq = [1, 1, 1];
11 % beq = 7;
12 %[x, fval] = linprog(c, A, b, Aeq, beq, LB, UB, X0,
13 %OPTIONS)，fval返回目标函数的值，LB和UB分别是x的下界和上界，x0是x的初始值，options是控制参数
14 % x = linprog(-c, a, b, aeq, beq, zeros(3, 1))%zeros(3, 1)是LB
15 % value = c' * x
16 % [x, fval] = linprog(-c, a, b, aeq, beq, zeros(3, 1))
17 
18 % 无相等项
19 % c = [2; 3; 1];
20 % a = [1, 4, 2; 3, 2, 0];
21 % b = [8; 6];
22 % [x, y] = linprog(c, -a, -b, [], [], zeros(3, 1))
23 
24 %%循环搜索a
25 % a = 0;
26 % hold on%只要hold in在循环之前或循环中，就可以发挥作用
27 % while a < 0.05
28 %     c = [-0.05, -0.27, -0.19, -0.185, -0.185];
29 %     A = [zeros(4, 1), diag([0.025, 0.015, 0.055, 0.026])];%diag创建对角矩阵或获取矩阵的对角元素
30 %     b = a * ones(4, 1);
31 %     Aeq = [1, 1.01, 1.02, 1.045, 1.065];
32 %     beq = 1;
33 %     LB = zeros(5, 1);
34 %     [x, Q] = linprog(c, A, b, Aeq, beq, LB);
35 %     Q = -Q;
36 %     plot(a, Q, '*r');
37 %   
38 %     a = a + 0.001;
39 % end
40 % xlabel('a'), ylabel('Q')
41 %