How to combine cell arrays to form one nested cell array entry

Hello, I have a variable (X) that is a cell array (size 64X634). In the each location of cell array X, there is a nested 1x2 cell array.

How can I combinethe nested 1x2 cell arrays across the 634 columns in X such that the variable(X) is now the desired size of 64x1, where each row entry of the cell arrray X contains the new 634x2 nested cell array?

In other words, I want to combine each of the 1x2 cell arrays found in the columns of the original variable(X) so that each row of variable(X) only has one column (now a nested cell array with all the original 1x2 nested cell arrays). Thanks!

Answer 1

[Voss]

% 4x3 instead of 64x634, for demonstration
X = { ...
    {1 2} {3 4} {5 6}; ...
    {7 8} {9 10} {11 12}; ...
    {13 14} {15 16} {17 18}; ...
    {19 20} {21 22} {23 24}; ...
    };
X

X = 4x3 cell array
    {1x2 cell}    {1x2 cell}    {1x2 cell}
    {1x2 cell}    {1x2 cell}    {1x2 cell}
    {1x2 cell}    {1x2 cell}    {1x2 cell}
    {1x2 cell}    {1x2 cell}    {1x2 cell}

X{1,1},X{1,2},X{1,3}

ans = 1x2 cell array
    {[1]}    {[2]}

ans = 1x2 cell array
    {[3]}    {[4]}

ans = 1x2 cell array
    {[5]}    {[6]}

N = size(X,1);
Y = cell(N,1);
for ii = 1:N
    Y{ii} = vertcat(X{ii,:});
end
X = Y;

X

X = 4x1 cell array
    {3x2 cell}
    {3x2 cell}
    {3x2 cell}
    {3x2 cell}

X{1}

ans = 3x2 cell array
    {[1]}    {[2]}
    {[3]}    {[4]}
    {[5]}    {[6]}

[Alyssa]

Thank you! I had tried concat at first and it didn't work, vertcat works!

[Voss]

You're welcome!

You could also use cat(1,_), that is,

Y{ii} = cat(1,X{ii,:});

https://www.mathworks.com/help/matlab/ref/double.cat.html

https://www.mathworks.com/help/matlab/ref/double.vertcat.html

https://www.mathworks.com/help/matlab/ref/double.horzcat.html