Grouping elements in an array?

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Hello. I have a 1 x 46 struct array 'data' with two fields, 'Altitude' and 'Velocity'. Each array has different sizes but the corresponding two arrays for the two fields have same sizes. For example, when I type in:
counts = array(@(x) numel(x.Altitude), data)
counts =
Columns 1 through 19
100 335 104 74 294 101 0 ... until the column goes 46.
What I am trying to do is to group the elements of each arrays in 'Altitude' seven by seven and find the mean.Then, find the mean of the corresponding the elements in the 'Velocity' field. Then I would like to compare the each mean of the 'Altitude' arrays, and plot it.
Could anyone help me with this? Any help is greatly appreciated as I am clueless here. Thank you. The code I have written so far is:
for n = 1 : length(data)
interval_number = floor(length(data(n).Altitude)/7);
t = 0;
for k = 1 : interval_number
s1(n).a(k) = mean(data(n).Altitude(1+t:7+t));
s1(n).b(k) = mean((data(n).Velocity(1+t:7+t)));
t = t + 7;
end
end

Accepted Answer

Andrei Bobrov
Andrei Bobrov on 2 Jun 2015
Edited: Andrei Bobrov on 2 Jun 2015
x = struct2cell(data);
out = cellfun(@(y)nanmean(reshape([y,nan(1,mod(-numel(y,7))],7,...
[])),squeeze(x),'un',0);

More Answers (1)

Azzi Abdelmalek
Azzi Abdelmalek on 2 Jun 2015
Edited: Azzi Abdelmalek on 2 Jun 2015
v=struct('Altitude',num2cell(1:46),'Velocity',num2cell(randi(9,1,46)))
ii=0;
m=numel(v)
for k=1:7:46
ii=ii+1
k1=k
k2=min(m,k+6)
out(ii).Altitude=mean([v(k1:k2).Altitude])
out(ii).Velocity=mean([v(k1:k2).Velocity])
end
  2 Comments
bio lim
bio lim on 2 Jun 2015
Edited: bio lim on 2 Jun 2015
I am so sorry but I am a beginner in MATLAB. Could you help by explaining briefly your code, and tell if my code is still viable? Could you also explain why k = 1 : 7 : 10? Thanks!
Azzi Abdelmalek
Azzi Abdelmalek on 2 Jun 2015
No, it's for k=1:7:46

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