How to identify which cell has the minimum value in Matlab?

I currently have the following cell :

G=cell(4,2)

Each sell has a 2x1 double

Example :

[100;200]   [20;60]
[100;300]   [20;90]
[200;300]   [60;90]
[]  []      []  []

How can I identify which cell has the minimum value, (where the values compared are in the SECOND column) so that the addition is between 20;60 20;90 and 60;90 ?

I started typing out a code but got stuck :

for k=1:(4)
    add(k)=sum(cell2mat(G(k+4)))
end

(...Find a way to know which cell gave the minimum off `add` using min(add)...)

But then I don't how to identify which cell has the minimum .. The answer I'm looking for should indicate that the minimum value is at Column 2 Row 1 of cell G and hence : 20;60

Solution

G[{:}] will arrange (column-wise) the cell array to a 2D matrix (lines corresponding to the first and second element of each cell entry

ans =

   100   100   200    20    20    60
   200   300   300    60    90    90

You can then apply min accordingly to obtain the minimum value and a linear index on the cell, e.g.:

[minVal, minIndex] = min([G{:}], [], 2);

Update: Since the sum of elements is defined as minimum (L1 norm), you can use cellfun to detect empty entries and sum in each, before applying min over the resulting array:

indexEmpty = cellfun(@isempty, G)  % find empty entries of G
sumG = cellfun(@sum, G)            % apply sum on each entry of G 
sumG(indexEmpty) = nan;            % set empty entries to NaN (exclude from min) 
[minVal, minIndex] = min(sumG(:)); % return min and its location in sumG (and G)

Result: G{minIndex}

ans =

   20
   60

The linear index minIndex can be translated to array subscripts using ind2sub.

[i,j] = ind2sub(size(G), minIndex);

In this way you can index the array both using G{minIndex} (i.e., 5) and G{i,j} (i.e., 1,2).