how do I convert a cell array of different size cells to a matrix

suppose I have a cell array of cells:

c = {{1 2}; {1 2 3};{4 5 6};{10 11 12 12 14}};

What is the best way to convert this to a matrix?

This is what I have come up with:

M = max(cellfun(@numel, c));
c2 = cellfun(@(row)[row (cell(1,M-numel(row)))], c, 'uni', 0);
for idx = 1:numel(c2)
    c2{idx}(cellfun(@isempty, c2{idx})) = {0};
end
 c3=vertcat(c2{:});

this seems like an easy thing to do, but I feel I overcomplicated the code. Is this the best way to do it?

Ultimately I'm expecting to have a matrix array that looks like this:

     1     2     0     0     0
     1     2     3     0     0
     4     5     6     0     0
    10    11    12    12    14

my goal is to exclude the zeros and count the number of repeat occurences per column...

I.e. in the example above

col1UniqueSorted values = [1 4 10]
col1NumberOfHits=         [2 1  1]

col2UniqueSorted values = [2 5 11]
col2NumberOfHits=         [2 1  1]

etc ...

I managed to get the results I need, but just looking for a cleaner or better way to do it. if I can get the answer working directly with cells, I'm will to try that too, I just was not able to figure it out.

thanks

Answer 1

[Birdman]

Just one line, which is an improvement of your code:

maxEl=5;%max number of elements of a cell element in your cell
C=cell2mat(cellfun(@(x) [cell2mat(x) zeros(1,maxEl-numel(x))],c,'uni',0))

[Kafayat Olayinka]

what is x?

Answer 2

[Jos (10584)]

An easy job for padcat :)

c = {{1 2}; {1 2 3};{4 5 6};{10 11 12 12 14}} 
% rather awkward cell array of cell arrays of numeric arrays ...

% engine
c2 = cellfun(@(x) [x{:}], c, 'un',0) % convert to cell array of numeric array
[m, tf] = padcat(c2{:}) % concatenate, pad rows with NaNs
m(~tf) = 0 % replace NaNs by zeros

padcat can be downloaded from the File Exchange: https://uk.mathworks.com/matlabcentral/fileexchange/22909-padcat-varargin-

Answer 3

[dave]

Thanks for the comments

I have not tried padcat ... but I will give I try

thanks for the suggestion