How to extract element of all matrices within a cell array using cellfun?
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NS
el 6 de Dic. de 2018
Comentada: Image Analyst
el 16 de Abr. de 2023
I need to extract (2,1) i.e. second row and first column element of all matrices within cell array ?
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Respuesta aceptada
Image Analyst
el 6 de Dic. de 2018
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)
5 comentarios
Image Analyst
el 7 de Dic. de 2018
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
Más respuestas (2)
Jos (10584)
el 6 de Dic. de 2018
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(...)
5 comentarios
James Tursa
el 6 de Dic. de 2018
Editada: James Tursa
el 6 de Dic. de 2018
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
el 16 de Abr. de 2023
Hi I want to use all nested arrays inside each cell. Thank you for your help His photo is attached.
1 comentario
Image Analyst
el 16 de Abr. de 2023
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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