Can anyone provide a code for calculating autocorrelation without autocorr?

Can anyone provide a code for calculating autocorrelation without using autocorr as I do not have the econometrics toolbox?

[ASWIN SEKHAR C S]

https://in.mathworks.com/matlabcentral/fileexchange/133777-corrected-un-damped-autocorrelation-function-acf?s_tid=prof_contriblnk#add-tags-span

Answer 1

[Walter Roberson]

http://www.mathworks.com/matlabcentral/fileexchange/30540-autocorrelation-function--acf-

Answer 2

[Abdul Wasay]

x=input('Enter the first Sequence : ');
h=input('Enter the second sequence : ');

n=length(x);
m=length(h);
k=n+m-1;
x=[x zeros(1,k-n)]';
h=wrev(h);
h=[h zeros(1,k-m)]';
for i=1:k
c(:,i)=circshift(x,i-1);
end
y=c*h;
disp('Correlation of the sequences')
disp(y');

Answer 3

[i Wijayanto]

https://www.mathworks.com/matlabcentral/answers/11443-how-to-estimate-the-auto-correlation-function-value-r-k-e-x-n-x-n-k