access cell array inside another cell array

Hi,

a short question, I just can't get it running:

I have a 1x94 cell array called A with 94 600x27 cell array inside. Now, as an example, I want to access the following value: 2nd row, 3rd column, 4th cell array. How can I do that?

I want to avoid a "temporary variable" as in:

temp=A{4} value=temp(2,3)

Many thanks, Steffen

[Sean de Wolski]

Why do you have this data structure? What is the data and what are you trying to do? There might be a more efficient way.

Answer 1

[Titus Edelhofer]

Hi Steffen,

nested indexing should work:

A = cell(1,94);
A{4} = cell(600, 27);
b = A{4}{600,27}

Titus

[Steffen]

Thank you Titus, that gives me this error: Cell contents reference from a non-cell array object.

So I checked and the 1x94 cell array actually consists of a non-cell array. Their type is double...is it still possible to access them?

EDIT: I converted the rgular array to a cell array now (with num2cell), but if there's an option to access the array directly it would be preferred. Thank you already :)

[Michael Haderlein]

So what do you have inside the outer cell array A? Is it cells or doubles? If it's double, then access it by

 b=A{4}(600,27);

[Steffen]

Ah, I was blind and always tried

A{4}[600,27];

It works now! Thanks a lot!

[Hina Iqbal]

Hi Titus Edelhofer! i also have to access the data as it is but my problem is that data in each cell array vary.. e.g;

   [21x1 double]
   [32x1 double]
   [6x1 double]

then please tell me how to access data from this sort of data where the main cell array which contains this type of data is cell.

Answer 2

[N/A]

To access 2nd row column three of 4th cell try this code

temp = A{4}(2,3)

[monkeyquant]

How about this case?

>> A = {3,   9,     'a'; 
    'B', [2,4], 0};
>> A(:, 3) 

% which spits out 

ans =

2×1 cell array

{'a'}
{[0]}

Now I want to access entire row or columns values from this newly extractracted cell. I tried various approach but cause Error: Invalid array indexing. A couple of examples are below:

>> A(:, 3){:, 1}
>> A(:, 3){2, 1}

[Walter Roberson]

@monkeyquant

There is no direct way to do that. You need to either use a temporary variable or a helper function

A = {3,   9,     'a'; 
    'B', [2,4], 0};

%temporary variable
A3 = A(:,3);
A3(2,:)

ans = 1×1 cell array
    {[0]}

%helper function
SelectRow = @(object, row) object(row,:);
SelectRow(A(:,3), 2)

ans = 1×1 cell array
    {[0]}

The helper function only has to be created once for each context, not for every different place you want to do this kind of indexing.