How can I access element with same index from multiple cells

For example, we have

a = cell(2,2);
a{1} = 1:4;
a{2} = 1:4;
a{3} = 1:4;
a{4} = 1:4;

How can we access like

a{:}(1)

to extract all first elements in cells a ?

Answer 1

[Cedric]

 >> extract = @(C, k) cellfun(@(c)c(k), C) ;
 >> extract(a, 1)
 ans =
     1     1
     1     1
 >> extract(a, 3)
 ans =
     3     3
     3     3

if you want to make a lightweight function for extracting various elements of various cell arrays, or simply

 >> cellfun(@(c)c(1), a)
 ans =
     1     1
     1     1

if it is just for cell array a and you are fine with hard coding the element # in the expression.

[Hu]

Thanks!

[Cedric]

You're welcome.

Answer 2

[Arturo Moncada-Torres]

I suggest you to use cellfun, which applies a function to each element of a cell array. In your case, it would be something like this:

% Original cell.
a = cell(2,2);
a{1} = 1:4;
a{2} = 1:4;
a{3} = 1:4;
a{4} = 1:4;

% Choose element to extract.
elementToExtract = 1;

% Actually extract the chosen element of all the cells in a.
cellfun(@(x) x(elementToExtract ), a)

Hope it helps.

[Hu]

Thanks!