How to extract element of all matrices within a cell array using cellfun?
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I need to extract (2,1) i.e. second row and first column element of all matrices within cell array ?
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Image Analyst
2018년 12월 6일
Are all the matrices in the cells the same size? If so, just use cell2mat() and indexing:
[rows, columns] = size(ca{1})
m = cell2mat(ca)
m21 = m(2:rows:end, 1:columns:end)
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Image Analyst
2018년 12월 7일
Of course, you could always use a simple for loop:
output = ones(1, numel(ca));
for k = 1 : numel(ca)
thisCellsContents = ca{k}; % Extract this one particular cell
output(k) = thisCellsContents(2, 1);
end
추가 답변 (2개)
Jos (10584)
2018년 12월 6일
This looks like homework to me. Here is a big hint:
Create a function that extracts this for you and use cellfun to apply it to all cells ...
MyFun = @(M) M(...)
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James Tursa
2018년 12월 6일
편집: James Tursa
2018년 12월 6일
The value of the (2,1) element makes no differrence to indexing ... whether it is finite or inf or NaN. You will not get an "index exceeds" error just because the element is NaN. You get the error because there is no (2,1) element. You need to re-check your matrices. What do you get when you run this:
C = your cell array of matrices
min(cellfun(@numel,C))
min(cellfun(@(c)size(c,1),C))
Ali Nik
2023년 4월 16일
Hi I want to use all nested arrays inside each cell. Thank you for your help His photo is attached.
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Image Analyst
2023년 4월 16일
Not sure how this is an answer to @NS. And when you said "His photo is attached", we're not sure what photo you're talking about or where it is. Certainly NS's photo is not attached to your Answer.
If you have your own question, start a new question and attach your cell array in a .mat file after you read this:
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