For loop to create a matrix array
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Cutie
el 6 de Feb. de 2022
Comentada: Image Analyst
el 21 de Feb. de 2023
I have a data X say
X= 1:100 (integer 1 to 100)
I want to write a for loop that will create matrix of w=10x5 (10rows, 5 columns) where by column 1 will be the first 10 elements of X (1 to 10), column 2 (11 to 20) and so on and then stop at column 5 (41 to 50) before creating another matrix say w2 (ie starting the iteration again).
I don't want to use reshape function as it won't fit into the real data I am working on.
4 comentarios
Image Analyst
el 6 de Feb. de 2022
Editada: Image Analyst
el 6 de Feb. de 2022
For 90, what are the sizes of the two matrices?
- 9-by-5? (in which case, my answer below works)
- Or one matrix of 10-by-5 and the second one of 10-by-4?
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Matt J
el 6 de Feb. de 2022
Editada: Matt J
el 6 de Feb. de 2022
Because, I may need to create matrix of size 9 by 5. In which case I will only have 2 matrices formed from the first 90 elements (1:90) and the last 10 element can be discarded.
That doesn't disqualify reshape.
rows=9;
cols=5;
X=1:100;
M=rows*cols;
N=numel(X);
X=reshape( X(1:floor(N/M)*M) ,rows,cols,[]);
w=squeeze(num2cell(X,[1,2]))
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Image Analyst
el 6 de Feb. de 2022
Editada: Image Analyst
el 6 de Feb. de 2022
Try this
N = 100; % or 90 or some other multiple of 10
X= 1 : N; % (integer 1 to 100)
x1 = reshape(X(1:N/2)', N/10, [])
x2 = reshape(X(N/2+1:end), N/10, [])
If you don't want to use reshape for some weird reason, you can do it with a for loop but it will be more complicated.
X = 1 : 100;
x3 = zeros(10, 5);
x4 = zeros(10, 5);
k = 1;
for col = 1 : 5
for row = 1 : 10
x3(row, col) = X(k);
x4(row, col) = X(k + 50);
k = k + 1;
end
end
x3
x4
3 comentarios
Image Analyst
el 21 de Feb. de 2023
@Navita as you can see above there is an output. I ran it in the editor with the green run triangle and there is definitely an output. Just look at my Answer and you can see it.
If you don't have any output then you must have copied my code and changed it somehow.
If you have any more questions, then attach your data and code to read it in with the paperclip icon after you read this:
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