MATLAB: How to Put These Vectors in a Matrix

struct

A.B.G = [1 2 3];
A.C.G = [4 5 6];
A.D.G = [7 8 9];
A.E.G = [10 11 12];
A.F.G = [13 14 15];
so it will look like:
1  2  3
4  5  6
7  8  9
10 11 12
13 14 15
It's just an example and A has more than 5 fields, so please do not suggest something like this:
[A.B.G; A.C.G; A.D.G; A.E.G; A.F.G]

Best Answer

Here is one way:
>> A.B.G = [1 2 3];
>> A.C.G = [4 5 6];
>> A.D.G = [7 8 9];
>> A.E.G = [10 11 12];
>> A.F.G = [13 14 15];
>> cell2mat(structfun(@(s){s.G},A))
ans =
     1     2     3
     4     5     6
     7     8     9
    10    11    12
    13    14    15
Although to be honest your code would be much faster and simpler if you used a non-scalar structure, because then you can simply do this:
>> S(1).G = [1 2 3];
>> S(2).G = [4 5 6];
>> S(3).G = [7 8 9];
>> S(4).G = [10 11 12];
>> S(5).G = [13 14 15];
>> vertcat(S.G)
ans =
   1     2     3
   4     5     6
   7     8     9
  10    11    12
  13    14    15
Using indices will be much simpler than trying to access fieldnames, and woudl allow you to very simply solve your other question by using indices to select the parts of the structur that you want:
>> vertcat(S([1,3,4]).G)
ans =
     1     2     3
     7     8     9
    10    11    12
Do not make your code more complicated than it needs to be. Good data storage makes your code simpler and neater too.
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