Creating a matrix from the output of a variable inside a for loop

Question

I would like to enter the results of the following loop inside a matrix as its elements:

p=1;
q=4;

For[i = 0, i < p, i++,
  For[j = 1, j < q + 1, j++,
   For[h = 0, h < p, h++,
    For[k = 1 , k < q + 1, k++,
     Subscript[wtotal, m, i, j, h, k] = 
      Subscript[w, m, i, j, h, k  ] + Subscript[w1, m, i, j, h, k]
     ; Print[Subscript[wtotal, m, i, j, h, k]]]]
   ]
  ];

This matrix gives 16 values, so I would like to enter those 16 values inside a 4X4 matrix. So how should I do it...

Further how should i convert the 4x4x4x4 table into a 16x16 matrix so that i can take its inverse.?

Answer 1

You can either do an iterative addition:

p = 1; q = 4;
wtotal = Table[
  Subscript[w, m, i, j, h, k] + Subscript[w1, m, i, j, h, k], {i, 
   p}, {j, 2, q + 1}, {h, p}, {k, 2, q + 1}]

(since Mathematica starts indexing at 1, I've adjusted the iterators).

Or you can add the two tables directly:

p = 1; q = 4;
w = Table[
   Subscript["w", m, i, j, h, k], {i, p}, {j, 2, q + 1}, {h, p}, {k, 
    2, q + 1}];
w1 = Table[
   Subscript["w1", m, i, j, h, k], {i, p}, {j, 2, q + 1}, {h, p}, {k, 
    2, q + 1}];

wtotal = w + w1

Note that I used "w" instead of w inside subscripts to prevent a recursive calling.