convert structure class to double class

Let's say:

A : 4x1 structure class
A= Field1 :[1000x1 double],
   Field2 : [2x1 double], 
   Field3 : [5x1 double],
   Field4 : [1x1 double]

A= Field1 : [1;2;3...;1000],
   Field2 : [99;11], 
   Field3 : [44;11;33;88;66],
   Field4 : [77]

Question: How can i convert "structure A" to "double class B" for the last third double ?

_Result_: B=[99;11;44;11;33;88;66;77]

[Stephen23]

@ha ha: your example shows A is a cell array, not a structure.

[ha ha]

A is "structure class"

A is NOT "cell class".

Sorry.Plz see my edit

[Birdman]

Check my answer.

Answer 1

[Stephen23]

Fake data:

>> A.F1 = [1;2;3];
>> A.F2 = 4;
>> A.F3 = [5;6];
>> A.F4 = [7;8;9];

To concatenate all fields of a scalar structure you could convert to cell array using struct2cell as an intermediate step:

>> C = struct2cell(A);
>> cat(1,C{:})
ans =
   1
   2
   3
   4
   5
   6
   7
   8
   9

But most likely you would be much better off using a non-scalar structure, because then you can simply do this:

cat(1,A.field)

and also use simple-and-efficient indexing to access parts of the structure.

Answer 2

[Stephen23]

Using your example cell array:

>> A= {[99;11], [44;11;33;88;66], [77]};
>> cat(1,A{:})
ans =
                    99
                    11
                    44
                    11
                    33
                    88
                    66
                    77