How to replace cell values with consecutive values related to their index

For example:

a = 1x3 cell array

columns 1 through 3

{1x1} {1x5} {1x3}

I'd like to be able to replace the values in each cell array with consecutive values so that:

a = 1x3 cell array

{[1]} {[2 3 4 5 6]} {[7 8 9]}

Thanks!

Answer 1

[dpb]

c=[{cell(1,1)} {cell(1,5)} {cell(1,3)}];        % original cell array
% engine
n=cellfun(@numel,c);
v=1:sum(n);
i1=1;
for i=1:numel(n)
  i2=i1+n(i)-1;
  c{i}=v(i1:i2);i1=i2+1;
end

results in

>> c
c =
  1×3 cell array
    {[1]}    {1×5 double}    {1×3 double}
>> c{:}
ans =
     1
ans =
     2     3     4     5     6
ans =
     7     8     9
>> 

There's probably a clever accumarray() or arrayfun() syntax to avoid the explicit loop, but nothing came to me quickly...

[Dc215905]

Thank you!

That's way less convoluted than what I cam up with:

b = 0;
in = 1;
for i = 1:length(CellMatrix)
    c = b(end);
    b = [];
    for in = 1:length(CellMatrix{i})
        length(CellMatrix{i});
        b(end+1) = c + 1;
        c = c +1;
    end
    in = 1;
    CellMatrix(i) = {b};
end

Answer 2

[Stephen23]

Simpler:

C = {cell(1,1),cell(1,5),cell(1,3)}

C = 1×3 cell array
    {1×1 cell}    {1×5 cell}    {1×3 cell}

N = cellfun(@numel,C);
D = mat2cell(1:sum(N),1,N)

D = 1×3 cell array
    {[1]}    {[2 3 4 5 6]}    {[7 8 9]}

[dpb]

That's what I intended, but kept muffing the mat2cell syntax...it's always thrown me for a loop for some reason -- rarely ever use it I guess is likely cause.