How do I extract specific data from an array inside a cell array using indexing?

So I have a cell array B of size 4*101 in which each cell contains an array of size 1*3, like this:

B = cell([4 101]);
for i = 1:4
    for ii = 1:101
        B{i,ii} = rand([1 3]);
    end
end

And I need to get the third element of the 1*3 arrays from all cells in the top row of the cell array. I can do that using

C = zeros(101,1)
for i = 1:101
    C(i) = B{1,i}(3);
end

But since I need to extract this kind of data quite a lot it'd be a lot nicer to be able to do this in one line using indexing. I figured using

C = B{1,:}(3);

Should work but this gives the error

"Expected one output from a curly brace or dot indexing expression, but there were 101 results."

How do I index this so that it works?

Answer 1

[Mehmed Saad]

use cellfun

cellfun(@(x) x(3),B(1,:))

Answer 2

[Peng Li]

d = cellfun(@(x) x(3), B);

d gives you the third element from all cells. You can index into d to find those that correspond to the first row.

[Mehmed Saad]

ahahaha, same answer xD

Answer 3

[Ameer Hamza]

Use can use basic indexing operations in MATLAB without the need to call any function

B = cell([4 101]);
for i = 1:4
    for ii = 1:101
        B{i,ii} = rand([1 3]);
    end
end

result = [B{1,:}];
result = result(3:3:end);