Cell array....searching without a loop?
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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
Azzi Abdelmalek
2012-11-10
what do you mean appropriate point?
Azzi Abdelmalek
2012-11-10
编辑：Azzi Abdelmalek
2012-11-10
and you said 1 point from each cell, how can you store the result in 501x201x119? for me it's not clear
jenka
2012-11-10
Jan
2012-11-10
Do you mean cat(1, ...)? What should A{:}(i,j,k) do? It is no valid Matlan syntax.
回答（1 个）
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
You can do the same thing like this:
per_90_mat2 = prctile(cat(4,A{:}),90,4)
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