For loop confusion!

ind1 = 1:6;
for t2=1:size(mm_r,3);
    if t2 <= 6
        wt_r = mm_r(1:361,1:361,ind1);
        wint2_r(:,:,t2) = mean(wt_r,3); %wint2_r is of 361*361*6

          ind1 = ind1+6;
      else
      end      
  end

To calculate the sequential differences I want to write this part in for loop, but it is not working out the way i want lets say an_r of size 361*361*5

anom_90_84_r = wint2_r(:,:,2) - wint2_r(:,:,1);
anom_96_90_r = wint2_r(:,:,3) - wint2_r(:,:,2);
anom_02_96_r = wint2_r(:,:,4) - wint2_r(:,:,3);
anom_08_02_r = wint2_r(:,:,5) - wint2_r(:,:,4);
anom_15_08_r = wint2_r(:,:,6) - wint2_r(:,:,5);

[Sophia]

This is how i tried

for k = 1:size(wint2_r,3)
    if k >1
        anom_r = wint2_r(:,:,k)-wint2_r(:,:,(k-1));
        an_r(:,:,k-1) = anom_r;
    else
    end
end

[dpb]

Don't know that we can help simply on the basis of "it isn't working the way I want", sorry. What is the desired output from what input? Generally a (very small) sample case that illustrates numerically helps clarify what often is difficult describing solely in words.

[Weird Rando]

Just letting you know that you didn't really need the if statement if you just start the for loop at 2.

for k = 2:size(wint2_r,3)
        anom_r = wint2_r(:,:,k)-wint2_r(:,:,(k-1));
        an_r(:,:,k-1) = anom_r;
end

Basically, are you asking how to dynamically name variable to store data. So in the for loop you would do this

anom_90_84_r = wint2_r(:,:,2) - wint2_r(:,:,1);
anom_96_90_r = wint2_r(:,:,3) - wint2_r(:,:,2);
anom_02_96_r = wint2_r(:,:,4) - wint2_r(:,:,3);
anom_08_02_r = wint2_r(:,:,5) - wint2_r(:,:,4);
anom_15_08_r = wint2_r(:,:,6) - wint2_r(:,:,5);

Answer 1

[Chad Greene]

I think you can skip the loops and use diff:

an_r = diff(wint2_r,1,3);