How to rectify the error in this code?

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Sadiq Akbar on 27 May 2021
Commented: DGM on 28 May 2021
I found a code for ESPRIT algorithm as below but it gives me this error:
Undefined function or variable 'theatest3'.
Error in ESPRIT_1D_Thesis (line 76)
thetaest=[thetaest1 thetaest2 theatest3];
How can I rectify the error? My code is as below:
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Matlab Code for ESPRIT Algorithm
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
d=0.5;
lamda=1;
thetaest1=[];
thetaest2=[];
thetaest3=[];
for i=1:2500; % number for independent trials
M=8;%6; % number of antenna elements
N=200; % number of snapshot
%input data
data1=sign(2*rand(1,N)-1);
data2=sign(2*rand(1,N)-1);
data3=sign(2*rand(1,N)-1);
% Signal to Noise ratio
SNR1=2;
SNR2=2;
SNR3=2;
% transmitted signals.
s1=sqrt(10^(SNR1/10))*data1;
s2=sqrt(10^(SNR2/10))*data2;
s3=sqrt(10^(SNR3/10))*data3;
% Direction of Arrival (DOA) for three uncorrelated sources
theta1=(pi/180)*82;
theta2=(pi/180)*90;
theta3=(pi/180)*98;
% array response vector
i=1:M;
A1=exp(-1j*2*pi*d*(i-1)*cos(theta1));
A2=exp(-1j*2*pi*d*(i-1)*cos(theta2));
A3=exp(-1j*2*pi*d*(i-1)*cos(theta3));
% the observation vectors from the two subarrays
Z=eye(8);
J0=Z(1:7,:);
J1=Z(2:8,:);
L=[J0 ;J1];
u1=L*A1'*s1+L*A2'*s2+L*A3'*s3;
% add noise to the observation vector
n1=sqrt(.5)*randn(size(u1))+1j*sqrt(.5)*randn(size(u1));
X1=n1+u1; % the observation data
% Estimation of the cross spectral matrix.
Rxx=zeros(2*(M-1),2*(M-1));
for k=1:200;
Rxx=Rxx+X1(:,k)*X1(:,k)';
end;
Rxx=Rxx/200;
% Total Least Square Method.
% eigen decompostion
[V D]=eig(Rxx);
%form signal space
Es=V(:,[8:10]);
E=Es;
E0=E(1:5,1:3);
E1=E(6:10,1:3);
E2=[E0';E1']*[E0 E1];
%eigen decomposition for E2
[V1 D1]=eig(E2);
E12=V1(1:3,3:5);
E22=V1(3:5,3:5);
% eigen decomposition
H=-E12*inv(E22);
[V2 D2]=eig(H);
%Estimation of the Direction of Arrival (DOA) for incident sources.
% z=angle(D3);
z=angle(D); % Changed by Me due to error
Y=sort(diag(z));
angle_estim1=acos(Y(3,1)/pi)/pi*180;
angle_estim2=acos(Y(2,1)/pi)/pi*180;
angle_estim3=acos(Y(1,1)/pi)/pi*180;
thetaest1=[thetaest1 angle_estim1]; % This Gives Error because of thetaest1
thetaes2=[thetaest2 angle_estim2];
thetaest3=[thetaest3 angle_estim3];
end ;
thetaest=[thetaest1 thetaest2 theatest3];
span=[1:.1:130];
% Figure 3.4
% histogram plot
hist(thetaest,span);
ylabel('histogram');
xlabel('DOA(angle)');

DGM on 27 May 2021
It's just a typo
thetaest3
theatest3
DGM on 28 May 2021
I don't see the problem at a glance. I'm not familiar with the thing you're trying to calculate. Perhaps it would help to try to develop a simplified version of the code to try testing a minimal set of inputs. That might make it easier to find where it's going wrong. Sorry I can't be of more direct help here.