# defining the mean of a values inside a matrix

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Eddy Ramirez on 18 Apr 2021
Commented: Khalid Mahmood on 19 Apr 2021
Greetings,
I was trying to find a way to find the mean of the values inside the matrix. For example, [1,2,3,4,5,6] I want to find the average between 1 & 2/ 2&3/3&4/4&5 and so on
I tried to do a for-loop but It doesnt seemt to work when I compare the values to hand calculations
z18=(-length(theta)/2+(0:length(theta)))'*h; % Travel of total 18 layers %%%% 19 values due to neutral axis
z18t=((-length(theta)/2+(0:length(theta)))'*h)/2; %% I took this approach as well but it does not work
for t=1:length(z18)
tt=max(1,(t-1));
ttt=min(length(z18), t+1);
tttt(t)=mean(z18(tt:ttt));
end
Walter Roberson on 18 Apr 2021
movmean() ?

Walter Roberson on 18 Apr 2021
A = randi(9, [1 6])
A = 1×6
8 2 2 3 6 3
[A(1), A(1:end-1) + diff(A)/2, A(end)]
ans = 1×7
8.0000 5.0000 2.0000 2.5000 4.5000 4.5000 3.0000
Eddy Ramirez on 18 Apr 2021
this works as magic!
thank you

Khalid Mahmood on 18 Apr 2021
Edited: Khalid Mahmood on 18 Apr 2021
Further methods
1: movmean(matrix,windowsize) it calculates running mean but considers only windowsize elements
examples:
mm2=movmean(z18,2)
mm3=movmean(z18,3)
Using for loop to calculate running mean as [z18(1), (z18(1)+z18(2)/2, ( (z18(1)+z18(2) )/2+ z18(3) )/3,...]
mm=z18(1);
for p=2:length(z18)
mm(p)=(mm(p-1)+z18(p))/p;
end
Khalid Mahmood on 19 Apr 2021
And remember, In moving mean, last value of source vector is not copied in result. It is actually calculated. So moving mean methods, movmean, mm code (to rduce in a mean way), and vectorised cumsum./[1:src] methods are actual moving mean methods. Those are just different types of moving means