I used most of ideas but it did not work then with the help of what herohuyongtao said i reach to this idea which worked properly

 [nr,nc]=size(x)

Which nr is the number of rows thanks all of you.

This is identical to your last (now deleted) question, just use size instead of length:

D = cellfun(@(x)(size(x,1)), C)

But note that cellfun is just a wrapper for a for-loop so doing this does not avoid loops.

Note a better solution (from Luis Mendo's comment) is

[D, ~] = cellfun(@size, C)

This way you can get the number of rows and the number of columns in one shot:

[nr, nc] = cellfun(@size, c)

Since you are only interested in the number of elements, here is a simplified version of flatten.m that @Ansari linked to:

function n = my_numel(A)
    n = 0;
    for i=1:numel(A)
        if iscell(A{i})
            n = n + my_numel(A{i});
        else
            n = n + numel(A{i});
        end
    end
end

The result:

>> C = {{{1,2},{3,4,5}},{{{6},{7},{8}},{9}},10};
>> my_numel(C)
ans =
    10

EDIT:

If you are feeling lazy, we can let CELLPLOT do the counting:

hFig = figure('Visible','off');
num = numel( findobj(cellplot(C),'type','text') );
close(hFig)

Basically we create an invisible figure, plot the cell array, count how many "text" objects were created, then delete the invisible figure.

This is how the plot looks like underneath:

You need to access each member of the cell array separately, you are looking for the size of the data contained in the cell - the cell is the container. Two methods

for loop:

cell_content_lengths=zeros(1,length(a));
for v=1:length(a)
    cell_content_lengths(v)=length(a{v});
end

cellfun:

cell_content_lengths=cellfun(@length,a);

Any empty cells will just have length 0. To extend the for-loop to matrices is trivial, and you can extend the cellfun part to cells containing matrix by using something like this, if you are interested:

cell_content_sizes=cell2mat(cellfun(@length,a,'uniformoutput',false));

(Note for the above, each element of a needs to have the same dimension, otherwise it will give errors about concatenating different size matrices)

EDIT

Based on your comment I think I understand what you are looking for:

non_empty_cols = sum(~cellfun(@isempty,a),2);

With thanks to @MZimmerman6 who understood it before me.

If textscan finds strings it returns a cell array of one or multiple cell arrays. The number of specifiers (in your case %s) you search for defines the number of nested cell arrays it returns. Most primitive solution for your case, where you only search for %s would be:

 d = size(alltext{1});

cellfun('length',a)

"apply length(x) to each element x in a".

cellfun docs.

You should use the size function:

nRows = size(myMatrix, 1);  % 1 stands for the first dimension