How can I convert cell array to an arrary matrix?

Hi,

I have a cell array and I want to ceovert it to an array matrix.

Can I convert this cell array as follows:

array_matrix = [6 11 20 12 15 19 12 4 18 16 3 13 1 14 7 8 5 10 9 17]

Is there a way to do this?

My cell matrix is attached.

[Stephen23]

"Is there a way to do this?"

https://www.mathworks.com/help/matlab/matlab_prog/comma-separated-lists.html

https://www.mathworks.com/matlabcentral/answers/1656435-tutorial-comma-separated-lists-and-how-to-use-them

OR

https://www.mathworks.com/help/matlab/ref/cell2mat.html

Answer 1

[Dyuman Joshi]

in = load('cell_array.mat')

in = struct with fields:
    ans: {[4×1 double]  [15]  [2×1 double]  [4]  [18]  [16]  [3]  [2×1 double]  [14]  [2×1 double]  [3×1 double]  [17]}

x = in.ans;

out = vertcat(x{:}).'

out = 1×20

6 11 20 2 15 19 12 4 18 16 3 13 1 14 7 8 5 10 9 17

[Dyuman Joshi]

On a side note, you should not use "ans" as a variable, as it can cause confusion and bugs/issues.

[Abdullah Türk]

Thank you Dyuman Joshi. It works.

[Dyuman Joshi]

You're welcome!

Answer 2

[Sulaymon Eshkabilov]

This is how it can be attained:

A = load('cell_array.mat').ans;
for ii = 1:numel(A)
    H = A{ii};
    K{ii} = cat(1, H(:)');
end
array_matrix = (horzcat(K{:}))

array_matrix = 1×20

6 11 20 2 15 19 12 4 18 16 3 13 1 14 7 8 5 10 9 17

[Abdullah Türk]

x = load('cell_array.mat').ans;

Sulaymon Eshkabilov thank you for your response.

The code above is not work. It gives this error:

Undefined variable "load" or class "load".
Error in Untitled (line 8)
x = load('cell_array.mat').ans;

Thanks again.

[Walter Roberson]

temp = load('cell_array.mat');
A = temp.ans;

[Abdullah Türk]

Thank you Walter. It work now.

Answer 3

[Voss]

@Abdullah Türk: If you know that all the cells of your cell array contain column vectors of the same class (as is the case in the variable ans in the posted mat file), then @Dyuman Joshi's approach will work:

x = load('cell_array.mat').ans;
out = vertcat(x{:}).'

out = 1×20

6 11 20 2 15 19 12 4 18 16 3 13 1 14 7 8 5 10 9 17

Alternatively, if the cells can contain arrays of any shape and dimensionality (still of the same class), then you'll need to reshape them before doing the vertical concatenation (vertcat). For example:

x = load('cell_array.mat').ans;
x_col = cellfun(@(m)reshape(m,[],1),x,'UniformOutput',false);
out = vertcat(x_col{:}).'

out = 1×20

6 11 20 2 15 19 12 4 18 16 3 13 1 14 7 8 5 10 9 17

[Abdullah Türk]

Voss, thank you very much for your detailed information.

The following code is not work. I think this has something to do with the MATLAB version I use. I'm sure the code you wrote works, but I think it didn't work in my version.

x = load('cell_array.mat').ans;

Thanks a lot again.