Assigning multiple variables vectors from a cell array
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I'm wondering if there is any smart solution on how to access multiple same-sized vectors inside of a cell array and assign them to an independent variable.
cellArray =
1×4 cell array
{1×101 double} {1×101 double} {1×101 double} {1×101 double}
Thanks!
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Accepted Answer
Honglei Chen
on 13 Dec 2017
Edited: Honglei Chen
on 13 Dec 2017
I would just do the following and then access them using 3rd indices
reshape(cell2mat(cellArray),[size(cellArray{1}) length(cellArray)])
HTH
2 Comments
More Answers (2)
Adam
on 13 Dec 2017
[a1, a2, a3, a4] = cellArray{:};
It is not advisable generally to do this, but for the record, that syntax should work. Having 1 variable is almost always a lot better than 4.
2 Comments
Stephen23
on 14 Dec 2017
Edited: Stephen23
on 14 Dec 2017
"...although one would have to look for a way to dynamically create as much variables as needed since the number of vectors in the cell array varies."
No, that is exactly what one should avoid doing. Magically creating or accessing variables will make your code slow, complex, buggy, obfuscated, hard to debug, and insecure. Read this to know why:
Adam already told you a much better solution, which is to keep your data in one array.
Jan
on 13 Dec 2017
Edited: Jan
on 13 Dec 2017
Do you mean:
a = cellArray{1}{1};
b = cellArray{2}{1};
c = cellArray{3}{1};
d = cellArray{4}{1};
Now a,b,c,d are 1x101 vectors.
3 Comments
Stephen23
on 14 Dec 2017
"...but this does not automatically match the varying number of vectors in the cell array."
Magically creating variables would be slow, complex, inefficient, hard to debug, and insecure. Using indexing is simple, neat, easy to debug, and very efficient.
Jan
on 14 Dec 2017
Edited: Jan
on 14 Dec 2017
@Johannes: Your question looks, like you have a nested cell:
cellArray =
1×4 cell array
{1×101 double} {1×101 double} {1×101 double} {1×101 double}
Therefore I've added the {k}{1}. As Stephen has pointed out: Such an automagical creation of variables is a bad programming pattern, which is known to cause more troubles than it solves.
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