Automate an averaging process and store info into an array

I have a code that takes the average of every 2 points of an array by changing k:

mdata = [1:10]; 
n1 = 1;
k = 1;
    
for n = 1:length(mdata)
    ma(n) = (1/(k + 1)) * sum(mdata(n1:n1 + k));
    n1 = (n1 + k) + 1;
    std_ma = std(ma);
end

I want to be able to automate a process that increases the averaging size each time (ex: 2 points averaged each time of an array, then 3 points averaged each time of an array, 4 points averaged, … n points averaged) and then stores all of that averaged data into a single array.

For example, if we have 2000 data points and we take the average of every 2 points, we’d end up with 1x1000. Then if we do 3 points averaged, we get 1x666~, 4 averaged we get 1x500, etc. I want to automate this and have all of that information stored into a single array.

Not sure how to go about it, any help?

Answer 1

[Keshav]

Hi, Based on my understanding you want to first calculate the average of 2 elements, 3 elements,... n elements. so if the array is [1 2 3 .... 10] then you want to make an array ans such that

ans = [avg(1,2) avg(3,4) .... avg(9,10) avg(1,2,3) avg(4,5,6) avg(7,8,9) avg(1,2,3,4) ................... avg(1,2,3,4,....,10)]

as you have already written the code to find the average of two elements, I made it generalize for every possible k.

clc
clear
mdata = [1:10];
n1 = 1;
n = 1;
for k=1:length(mdata)-1
    n1 = 1;
    while n1+k <= length(mdata)
        ma(n) = (1/(k + 1)) * sum(mdata(n1:n1 + k));
        n1 = (n1 + k) + 1;
        std_ma = std(ma);
        n = n + 1;
    end
end
ma

[zen]

exactly what I wanted, thanks! one question though, I want to be able to log the info in regards to k, where I changed ma(n) to ma(n,k) and get a 17x9 array which is what I want, however the array includes a ton of unwanted zeroes. For example:

clc
clear
mdata = [1:10];
n1 = 1;
n = 1;
for k = 1:length(mdata) - 1
    n1 = 1;
    while n1 + k <= length(mdata)
        ma(n,k) = (1/(k + 1)) * sum(mdata(n1:n1 + k));
        n1 = (n1 + k) + 1;
        std_ma = std(ma);
        n = n + 1;
    end
end
ma

ma = 17×9

1.5000 0 0 0 0 0 0 0 0 3.5000 0 0 0 0 0 0 0 0 5.5000 0 0 0 0 0 0 0 0 7.5000 0 0 0 0 0 0 0 0 9.5000 0 0 0 0 0 0 0 0 0 2.0000 0 0 0 0 0 0 0 0 5.0000 0 0 0 0 0 0 0 0 8.0000 0 0 0 0 0 0 0 0 0 2.5000 0 0 0 0 0 0 0 0 6.5000 0 0 0 0 0 0

I don't want any of the extra zeroes, just the values themselves in the same 17x9 formatted array. How would I go about this?

[Keshav]

you can use the below code to remove the extra zero. Just you have to reinitialize the value of n.

clc
clear
mdata = [1:10];
for k=1:length(mdata)-1
    n1 = 1;
    n = 1;
    while n1+k <= length(mdata)
        ma(n,k) = (1/(k + 1)) * sum(mdata(n1:n1 + k));
        n1 = (n1 + k) + 1;
        std_ma = std(ma);
        n = n + 1;
    end
end
ma

ma = 5×9

1.5000 2.0000 2.5000 3.0000 3.5000 4.0000 4.5000 5.0000 5.5000 3.5000 5.0000 6.5000 8.0000 0 0 0 0 0 5.5000 8.0000 0 0 0 0 0 0 0 7.5000 0 0 0 0 0 0 0 0 9.5000 0 0 0 0 0 0 0 0