LP error the number of rows of A must be the same with b

2 次查看（过去 30 天）
Nikolas Spiliopoulos
评论： Nikolas Spiliopoulos 2018-2-26
Hi again,
I am trying to run and LP optimization.
However, I am getting the following error
"The number of rows in A must be the same as the number of elements of b."
The problem is that the size of my matrices are: A [8X8] and b[8x1], so I don't really get where the error is
can you help?
thanks
Nikolas
  4 个评论
显示 2更早的评论
Nikolas Spiliopoulos
Nikolas Spiliopoulos 2018-2-23
if
clc;
clear;
close all;
N=2;
%equality constraint => x1+x2+y1+y2=[100; 50;70; 40;60] %x1=SoC1, x2=SoC2,
%y1=I1, y2=I2;
Initial_array=[100; 50;70; 40;60];
Soc1=eye(N);
Soc2=eye(N);
I1=eye(N);
I2=eye(N);
M1=[Soc1,2*Soc2,3*I1,I2];
M2=zeros(1,size(M1,2));
M2(1)=1;
M3=zeros(1,size(M1,2));
M3(N+1)=1;
M4=zeros(1,size(M1,2));
M4(2*N+1)=1;
M5=zeros(1,size(M1,2));
M5(3*N+1)=1;
Aeq=[M1;M2;M3;M4;M5];
beq=[zeros(N,1);12;15;5;10];
%Inequality constaints: 0<x1,x2<100, 0<y1,y2<45
A=eye(4*N);
b=[100*ones(2*N,1); 45*ones(2*N,1)];
lb=zeros(4*N,1);
%LP -> Objective function -> 3*x1+2*x2-5y1-3y2=0
options = optimoptions('linprog','Algorithm','interior-point');
ee=ones(1,N);
f=[3*ee,-2*ee,-5*ee,-3*ee ];
x=zeros(4*N,1);
x0=x;
[x,fval]=linprog(f,x0,A,b,Aeq,beq,lb,[],options);
end
Nikolas Spiliopoulos
Nikolas Spiliopoulos 2018-2-23
Error using linprog (line 232) The number of rows in A must be the same as the number of elements of b.
Error in LP_example (line 56) [x,fval]=linprog(f,x0,A,b,Aeq,beq,lb,[],options);

请先登录，再进行评论。

请先登录，再回答此问题。

回答（1 个）

Jan
Jan 2018-2-23
The calling sequence is (see doc linprog)
[x,fval] = linprog(f,A,b,Aeq,beq,lb,ub,options)
Your code:
[x,fval] = linprog(f,x0,A,b,Aeq,beq,lb,[],options)
What is x0? It seems to be misplaced here and linprog compare the sizes of x0 and A instead of A and b.
  3 个评论
显示 1更早的评论
Jan
Jan 2018-2-23
编辑：Jan 2018-2-23
When I run it, I get: "The problem is infeasible. Linprog stopped because no point satisfies the constraints." Which Matlab version are you using?
I'm confused also. In doc linprog I find:
[x,fval,exitflag,output,lambda] = linprog(f,A,b,Aeq,beq,lb,ub,options)
In the source of linprog.m it is:
[x,fval,exitflag,output,lambda] = linprog(f,A,B,Aeq,Beq,lb,ub,x0,options)
^^ ???
So try this (dangerous: PURE GUESSING!)
[x,fval]=linprog(f,x0,A,b,Aeq,beq,lb,[],[],options);
Sorry, I suggest a gunshot programming method.

请先登录，再进行评论。

类别

在 Help Center 和 File Exchange 中查找有关 Solver Outputs and Iterative Display 的更多信息

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by