Question

This is more Computer Science, but you could use series to solve this, if you can try a for loop
Global = zeros(nodos)
Global(1,1)= K(1,1,1)
Global(1,2)= K(1,2,1)
Global(2,1)= K(2,1,1)
Global(2,2)= K(2,2,1)+ K(1,1,2)
Global(2,3)= K(1,2,2)
Global(3,2)= K(2,1,2)
Global(3,3)= K(2,2,2)+ K(1,1,3)
Global(3,4)= K(1,2,3)
Global(4,3)= K(2,1,3)
Global(4,4)= K(2,2,3)+ K(1,1,4)
Global(4,5)= K(1,2,4)
Global(5,4)= K(2,1,4)
Global(5,5)= K(2,2,4)+ K(1,1,5)
Global(5,6)= K(1,2,5)
Global(6,5)= K(2,1,5)
Global(6,6)= ....

Note K(i,j,p) ; p = nodos-1

Answer 1

What is the question?