<a href="http:&#x2F;&#x2F;www.amazon.com&#x2F;Applied-Numerical-Linear-Algebra-Demmel&#x2F;dp&#x2F;0898713897&#x2F;" rel="nofollow">http:&#x2F;&#x2F;www.amazon.com&#x2F;Applied-Numerical-Linear-Algebra-Demme...</a><p>Numerical linear algebra has a long and vast history. You really do need specialized information that your undergrad linear algebra classes would not have imparted.<p>For instance, the condition number is important:
<a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Condition_number" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Condition_number</a>