What's wrong with my code? Error using * Incorrect dimensions for matrix multiplication

[Laihhhh (Huan Lai)]

The error.

Error using  * 
Incorrect dimensions for matrix multiplication. Check that the number of columns in the first matrix matches the number of rows in the second matrix. To
perform elementwise multiplication, use '.*'.

Error in cvxprob/eliminate (line 137)
            P       = P * cvx_invert_structure( xR );

Error in cvxprob/solve (line 18)
[ At, cones, sgn, Q, P, dualized ] = eliminate( prob, true, shim.dualize );

Error in cvx_end (line 88)
        solve( prob );

Error in svm_primal_2 (line 78)
cvx_end

Error in opt_phase_shift_matrix (line 168)
[V] = svm_primal_2(para,h_RU,h_RE,h_iR,h_iU,h_iE,h_UE,h_UR,para.M+1,S,scheduling2,transmit_p,jamming_p);

Error in main (line 114)
[theta_t, sec_rate2] = opt_phase_shift_matrix(para,h_hat,Theta,Q_r,Z_0,scheduling2,transmit_p,jamming_p);

The code.

function [V] = svm_primal_2(para,h_RU,h_RE,h_iR,h_iU,h_iE,h_UE,h_UR,M,S,scheduling2,transmit_p,jamming_p)
sigma2 = 10^(para.sigma2_dBm/10)/1000;
sigma_RSI2 = 10^(para.sigma2_dBm/10)/1000;

Tao_0 = zeros(para.K,para.T);
cvx_begin
cvx_solver mosek

%cvx_begin  sdp

variable X(M,M,para.T) complex
variable miu(1,para.T) nonnegative 
variable S(M,M,para.T) complex
variable Tao(para.K,para.N)
variable elta nonnegative
expression secRate(para.K,para.N);
for k = 1:para.K
    for n = 1:para.T 
        if scheduling2(k,n) > 0
            AW_1 = (transmit_p(n)/(sigma2+jamming_p(n)*sigma_RSI2))*diag(conj(h_RU(:,n)'))*conj(h_iR(:,k))*(h_iR(:,k).')*diag(h_RU(:,n)');
            AW_2 = (transmit_p(n)/(sigma2+jamming_p(n)*sigma_RSI2))*diag(conj(h_RU(:,n)'))*conj(h_iR(:,k))*(h_iE(k).');
            AW_3 =  (transmit_p(n)/(sigma2+jamming_p(n)*sigma_RSI2))*conj(h_iU(k,n))*(h_iR(:,k).')*diag(h_RU(:,n)');
            G_W = [AW_1,AW_2;AW_3,0];
            h_W = transmit_p(n) * conj(h_iU(k,n)) * h_iU(k,n);
            secRate(k,n) =  log(1+real(trace(G_W*S(:,:,n))+h_W))./ log(2) - real(Tao(k,n))/((1+Tao_0(k,n))*log(2));
        end
    end
end
throughput_sec = sum(secRate,2);
maximize(elta)

subject to

throughput_sec >= elta %max-min

for k = 1:para.K
    for n = 1:para.T
        if scheduling2(k,n) > 0
            AI_1 =  (transmit_p(n))*diag(conj(h_RE'))*conj(h_iR(:,k))*(h_iR(:,k).')*diag(h_RE');
            AI_2 =  (transmit_p(n))*diag(conj(h_RE'))*conj(h_iR(:,k))*(h_iE(k).');
            AI_3 =  (transmit_p(n))*conj(h_iE(k))*(h_iR(:,k).')*diag(h_RE');
            AU_1 =  (jamming_p(n))*diag(conj(h_RE'))*conj(h_UR(:,n))*(h_UR(:,n).')*diag(h_RE');
            AU_2 =  (jamming_p(n))*diag(conj(h_RE'))*conj(h_UR(:,n))*(h_UE(n).');
            AU_3 =  (jamming_p(n))*conj(h_UE(n))*(h_UR(:,n).')*diag(h_RE');
            G_I = [AI_1,AI_2;AI_3,0];
            G_U = [AU_1,AU_2;AU_3,0];
            h_U = jamming_p(n) * conj(h_UE(n)) * h_UE(n);
            h_I = transmit_p(n) * conj(h_iE(k)) * h_iE(k);
            real(trace(G_I*X(:,:,n)) + miu(n).*h_I) <= real(Tao(k,n));
            trace(G_U*X(:,:,n)) + miu(n).*(h_U)+miu(n).*sigma2 == 1;
        end
    end
end
for n = 1:para.T
    for z =1:M
        for i = 1:M
            for j  = 1:M
                if i == j && z == i && z == j
                    trace(X(i,j,n)) == miu(n);       
                end
            end
        end
    end
end
for n = 1 : para.T
    S(:,:,n) == semidefinite(M);
    X(:,:,n) == semidefinite(M);
    miu(n) >= 0
end  

V = X;
cvx_end

I have checked that there is not problem with matrix dimension. But I don’t know why.

I’ll appreciate if there is anyone could found the way to solve this problem.

I had tested and founded that three subjects would lead to this problem.

real(trace(G_I*X(:,:,n)) + miu(n).*h_I) <= real(Tao(k,n));
trace(G_U*X(:,:,n)) + miu(n).*(h_U)+miu(n).*sigma2 == 1;
trace(X(i,j,n)) == miu(n);

But I still don’t understand.

[Mark_L_Stone]

There may be something wrong in your installation, or your MATLAB session got corrupted. What happens if you try a different solver?

Try it in a new MATLAB session. if that doesn’t resolve the problem, reinstall CVX, and make sure you use CVX 2.2.

[Laihhhh (Huan Lai)]

All solutions above I’ve tried.
It’s still ’
Error using *
Incorrect dimensions for matrix multiplication. Check that the number of columns in the first matrix matches the number of rows in the second matrix. To perform elementwise multiplication, use ‘.*’.’

[jackfsuia (Jack)]

It might be that you overloaded some functions of CVX. For example, you might have defined a “min” function which clash with the CVX’s “min” funcition. To solve this conflict, you can click “set path” in MATLAB, select all CVX-related paths, move them to the top of the path list so that they will have the highest priority.

[Laihhhh (Huan Lai)]

Thanks! It’s a great solution.

[Laihhhh (Huan Lai)]

I tried adding real operation to the left and right sides of the equal sign in the problematic formula, and the above error was not reported. I would like to know why this is done and it can solve the problem. I would really appreciate it if you could take the time to answer my question.

real(trace(E_2 .* X(:,:,n))) == real(miu(n));

[Mark_L_Stone]

I don’t know what is going on here.

[Laihhhh (Huan Lai)]

Thanks a lot!