* Diagonal Dominance
Suppose that A \in R^{n \times n} is diagonally dominant then Gaussian eliminiation of A produces no zero pivot
elements.

Def. A \in R^{n \times n} is diagonally dominant if for each i=1,2,...n |a_{i,i}| \geq \Sigma_{j=1}^n |a_i,j|


* To test solution code:
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          [1]
Set y =   [\cdots]    \in R^n
          [1]]

Compute b=Ay
Solve Ax=b