Merge nx3 double matrices present within a 3x1 cell

I have the following generic code that generates me a 3x1 "output" cell.

a=randi(100,157,2);
b=randi(200,189,2);
c=randi(300,183,2);
mat={a;b;c};
for i=1:size(mat,1)
    if i==1
        aaa(i)={[mat{i,1} repmat(100,size(mat{i,1},1),1)]};
    elseif i==2
        aaa(i)={[mat{i,1} repmat(150,size(mat{i,1},1),1)]};
    elseif i==3
        aaa(i)={[mat{i,1} repmat(200,size(mat{i,1},1),1)]};
    end
end
output=aaa';

The internal of "output" is characterized by:

157x3 double
189x3 double
183x3 double

I would like to try to merge all the matrix (nx3), present inside "output", into one array (an example like this: link)

I used the following code but it gives an error due to the fact that the number of rows in each matrix is different.

matrix = [];
for nbr = 1:3
    matrix = [matrix, output{nbr,1}];
end

[Stephen23]

Simpler code and much more efficient use of MATLAB:

a=randi(100,157,2);
b=randi(200,189,2);
c=randi(300,183,2);
tmp = {a,b,c};
vec = [100,150,200];
for k = 1:numel(tmp)
    tmp{k}(:,3) = vec(k);
end
out = vertcat(tmp{:}) % comma-separated list

out = 529×3

59 31 100 58 60 100 35 98 100 65 48 100 97 91 100 56 49 100 94 77 100 33 4 100 11 89 100 4 56 100

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

Answer 1

[C B]

a=randi(100,157,2);
b=randi(200,189,2);
c=randi(300,183,2);
mat={a;b;c};
for i=1:size(mat,1)
    if i==1
        aaa(i)={[mat{i,1} repmat(100,size(mat{i,1},1),1)]};
    elseif i==2
        aaa(i)={[mat{i,1} repmat(150,size(mat{i,1},1),1)]};
    elseif i==3
        aaa(i)={[mat{i,1} repmat(200,size(mat{i,1},1),1)]};
    end
end
output=aaa';

matrix = [];
for nbr = 1:3
    matrix = [matrix; output{nbr,1}];
end
matrix

matrix = 529×3

97 80 100 12 3 100 38 40 100 54 71 100 96 94 100 25 50 100 81 59 100 4 76 100 73 85 100 54 37 100