Hi Nick, 
To combine multiple GF arrays either vertically or horizontally, you can use MATLAB's built-in functions. Here's how you can do it: 
- Vertical Concatenation: To concatenate multiple GF arrays vertically, you can use MATLAB ‘vertcat’ function.  
                Below is a simple example of concatenating multiple GF arrays vertically:            
    gfArray1 = gf([1 0 1 1 0 0 1]); 
    gfArray2 = gf([0 1 1 0 1 1 0]); 
    combinedGFArrayV = vertcat(gfArray1, gfArray2); 
    disp(combinedGFArrayV);   
  2x7 gf array with properties:
            x: [2x7 uint32]
            m: 1
    prim_poly: 3
-  Horizontal Concatenation: To concatenate multiple GF arrays horizontally, you can use MATLAB ‘horzcat’ function. 
                Below is an example of concatenating multiple GF arrays horizontally:                
     gfArray1 = gf([1 0 1 1 0 0 1]); 
     gfArray2 = gf([0 1 1 0 1 1 0]); 
     combinedGFArrayH = horzcat(gfArray1, gfArray2); 
     disp(combinedGFArrayH);
  1x14 gf array with properties:
            x: [1 0 1 1 0 0 1 0 1 1 0 1 1 0]
            m: 1
    prim_poly: 3
 
 
For further information about ‘vertcat’ and ‘horzcat’, please follow the MATLAB documentations given below. 
 
Hope this solves your query.