Hi all

I get this error when I run the code, please help me.

```
clc;clear ;close all;
% Simulation parameters
M = 8 ; % # of BS antenna
N = 2 ; % # of User antennas
K = 4; % # of Users
eta = 0.8; % energy conversion coefficient
sigma2 = 1 ; % The noise covariance at the ID receiver(watt)
%epsilon = 3 ; % pathloss exponent
RT = 4 ; % The target transmission rate(Mbps)
Bs = 10; %The bandwidth is 100 KHz
QOS = RT/Bs; %0.4(Mbps/Hz)
Pth_dBm = 46; %transit power threshold(dBm)
Pth = 10^(Pth_dBm/10)/1000;%mw
alpha = rand(1,K);% power splitting ratio
p = (Pth/K)*ones(1,K); % power splitting ratio
%%XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
%% Simulation
%% Modeling the Rayleigh fading channel(N*M)
num_ch=K*N;
H=randn(num_ch,M)+1i*randn(num_ch,M);
W_0=zeros(N,N,K);%initial W matrix
for ss=1:K
W_0(:,:,ss)=randn(N,N)+1i*randn(N,N);
end
thrsh=0.001; %the threshold for while loop stopping criteria.
diff=10;
while diff>=thrsh
% t calculation step.
t_j=zeros(1,K);
for x=1:K
Hj=H((x-1)*N+1:(x-1)*N+N,:);
Wj=W_0(:,:,x);
int_user=setdiff(1:K,x);
power_int=sum(p(int_user));
temp=(alpha(x)*power_int*trace(Hj'*Wj*Hj))^(-1)
t_j(1,x)=temp;
end
% cvx version for problem W
cvx_begin
variable W1(N,N) complex symmetric
[numel_SINR,denumel_SINR,cost]=Rate_m3(K,H,N,W1,t_j,alpha,sigma2,p);
maximize(cost)
subject to
for m=1:K
numel_SINR(1,m)-(2^QOS-1)*denumel_SINR(1,m)>=0
end
cvx_end
end
###########################
function[numel_SINR,denumel_SINR,cost]=Rate_m3(K,H,N,W1,t_j,alpha,sigma2,p)
cost=0;
numel_SINR=zeros(1,K);
denumel_SINR=zeros(1,K);
d=1;
Hj=H((d-1)*N+1:(d-1)*N+N,:);
pi_numel=setdiff(1:K,d);
alf=alpha(d);
Tmp=log_det(0.5*((alf*sum(p)*trace(Hj'*W1*Hj)+sigma2)+(alf*sum(p)*trace(Hj'*W1*Hj)+sigma2)'))-t_j(d)*alf*sum(p(pi_numel))*real(trace(Hj'*W1*Hj))+log_det(0.5*(t_j(d)+t_j(d)'))+1;
cost=cost+Tmp;
numel_SINR(1,d)=p(d)*alf*trace(Hj'*W1*Hj);
denumel_SINR(1,d)=alf*sum(p(pi_numel))*trace(Hj'*W1*Hj)+sigma2;
end
```