reading data in loop

I have some problem with reading data in loop

cx_sum(Q) and cy_sum(Q) are not working in loop.

cx_sum and cy_sum have value 1x1622.

for Q = 1:1621

CY_sum99 = mean(cy_sum(Q),'omitnan')

CX_sum99 = mean(cx_sum(Q),'omitnan')

end

So can you solve this problem? Thank you

Answer 1

[dpb]

But they are .. just that cy_sum(Q) is the single element of the array on each pass and the mean of a single number is the number and so the last computed value at the end of the loop is the last element of each array (if not NaN) .

You're looking for simply writing

CY_mn=mean(cy_sum,'omitnan');
CX_mn=mean(cx_sum,'omitnan');

probably...but that's guessing.

[Mingde]

thank you for you answer. if i want to change loop Q= 1:270. So are cy_sum and cx_sum working until 270? because I think if we don't need to put loop from start to end, it will show the whole data in there.

for Q = 1:270

CY_sum99 = mean(cy_sum,'omitnan')

CX_sum99 = mean(cx_sum,'omitnan')

end

I see cy_sum and cx_sum are working from 1:1622

so I want it to work in specific (start:end)

[dpb]

No, you don't want the loop still -- you want to sub-reference the portion of the array desired.

That would be

Nlower=1;            % programming practice -- don't bury "magic" numbers in code;
Nupper=270;          %  use variables that can change
CX_mn_UL=mean(cx_sum(Nlower:Nupper),'omintnan');

It doesn't matter over what elements you loop, the above computes the same result as the mean 270 times since you reference the full variable inside the loop.

I strongly recommend spending time reading the "Getting Started" tutorial section in the local documentation on MATLAB syntax and referencing arrays, etc., ...

[Mingde]

Thank you so much. I appreciate it your answer.