Cell array....searching without a loop?

Question

jenka 2012-11-10

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/53398-cell-array-searching-without-a-loop

I have a cell array A. Size is 200x1. The size of A{1} is 501x201x119=i x j x k. The same is true for other cells in A. Now for each point in dimension i that goes from 1 to 501, I need to extract appropriate point from each cell, and find 90 percentile of these points and save it into 501x201x119 array. Could you please help if you have elegant solution to this problem.

EDITED By Matt Fig to add (from an 'Answer' by jenka):

Let me make it more clear. Let's say, per Matt, suggestion

A = {rand(5,3,2);rand(5,3,2);rand(5,3,2);rand(5,3,2)};

Sorry I do not have a excess to matlab right now so this is pseudo code:

for j=1:3 
 for k=1:2
  B = [];
  for i=1:5
    B = cat(A{:}(i,j,k), B, 1); %not sure if we can do something like this
  end
  per_90_mat(i,j,k) = prcntile(B,90);
 end
end

4 个评论
显示 2更早的评论隐藏 2更早的评论

jenka 2012-11-10

Hi Azzi, I just replied below. Thank you!

Jan 2012-11-10

Do you mean cat(1, ...)? What should A{:}(i,j,k) do? It is no valid Matlan syntax.

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Matt Fig 2012-11-10

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/53398-cell-array-searching-without-a-loop#answer_65000

编辑：Matt Fig 2012-11-10

在 MATLAB Online 中打开

Post a simple, small example of the FOR loop you have been using to solve the problem. Say

A = {rand(5,3,2);rand(5,3,2);rand(5,3,2);rand(5,3,2)};

Now what are you doing with A?

EDIT

O.k., so it looks like you want to do something like this without the loops:

I = 5;
J = 3;
K = 2;
A = {randi(10,I,J,K);randi(10,I,J,K);randi(10,I,J,K)};
for jj=1:J
    for kk=1:K
        for ii=1:I
            B = cellfun(@(x) x(ii,jj,kk),A);
            per_90_mat(ii,jj,kk) = prctile(B,90); 
        end
    end
end