GEtting err0r

Getting error In Code

Unable to perform assignment because dot indexing is not supported for variables of this type.

x=optimvar('x',3,'LowerBound',[0, 0, -inf],'UpperBound',[inf, inf, inf]);
Obj=(x(1)-(2 *x(2))+3*x(3));
A =x(1)+x(2)+x(3)<=7;
B =-x(1)+x(2)-x(3)<=2;
C =3*x(1)-x(2)-2*x(3)==-5;
Problem=optimproblem('Objective',Obj,'ObjectiveSense','maximize');
Problem.Constraints.con_1 = A;
Problem.Constraints.con_2 = B;
Problem.Constraints.con_3 = C;
x0.x=[0 0 0]; 
[sol,xfval,exitflag,output] = solve(Problem,x0)

Unable to perform assignment because dot indexing is not supported for variables of this type.

pls Guide me

[Vivek]

Pls Guide me where i had made mistake

[Walter Roberson]

Code works for me here.

x=optimvar('x',3,'LowerBound',[0, 0, -inf],'UpperBound',[inf, inf, inf]);
Obj=(x(1)-(2 *x(2))+3*x(3));
A =x(1)+x(2)+x(3)<=7;
B =-x(1)+x(2)-x(3)<=2;
C =3*x(1)-x(2)-2*x(3)==-5;
Problem=optimproblem('Objective',Obj,'ObjectiveSense','maximize');
Problem.Constraints.con_1 = A;
Problem.Constraints.con_2 = B;
Problem.Constraints.con_3 = C;
x0.x=[0 0 0]; 
[sol,xfval,exitflag,output] = solve(Problem,x0)

Solving problem using linprog.
The dual-simplex algorithm uses a built-in starting point;
ignoring supplied X0.

Optimal solution found.

sol = struct with fields:
    x: [3×1 double]

xfval = 17.4000

exitflag = 
    OptimalSolution

output = struct with fields:
         iterations: 1
    constrviolation: 0
            message: 'Optimal solution found.'
          algorithm: 'dual-simplex'
      firstorderopt: 8.8818e-16
             solver: 'linprog'

sol.x

ans = 3×1

1.8000 0 5.2000

[Jan]

@Vivek: Please post the complete error message. Then we can see, in which line the code fails.

Answer 1

[Walter Roberson]

you have an existing numeric variable named x0 and so you not permitted to assign to x0.x because numeric variables cannot use dot indexing.

This is the kind of problem that using functions instead of scripts is designed to solve.