Assigning multiple variables vectors from a cell array

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!

Answer 1

[Honglei Chen]

I would just do the following and then access them using 3rd indices

reshape(cell2mat(cellArray),[size(cellArray{1}) length(cellArray)])

HTH

[Johannes Berger]

Thank you! Exactly what I was looking for.

[Jos (10584)]

Simple

cat(3, cellArray{:})

would do ...

Answer 2

[Adam]

[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.

[Johannes Berger]

Thank you, this solution does work, 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.

[Stephen23]

"...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:

https://www.mathworks.com/matlabcentral/answers/304528-tutorial-why-variables-should-not-be-named-dynamically-eval

Adam already told you a much better solution, which is to keep your data in one array.

Answer 3

[Jan]

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.

[Johannes Berger]

Using

cellArray{1}

already returned the first vector of the cell array. Using the 2nd indices returns an error. Of course, one could just use

a = cellArray{1};
b = cellArray{2};
c = cellArray{3};
d = cellArray{4};

but this does not automatically match the varying number of vectors in the cell array. Thanks for your help anyway!

[Stephen23]

"...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]

@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.