How to express the meaning I mention in one formula? There are two points: $(x_1,y_1),(x_2,y_2)$, if $|y_2-y_1|&gt;|x_2-x_1|$ then  $\tan(A)=\frac{|y_2-y_1|}{|x_2-x_1|}$  else if $|y_2-y_1|&lt;|x_2-x_1|$ then  $\tan(A)=\frac{|x_2-x_1|}{|y_2-y_1|}$

My question is, how to express the above meaning in one formula? what kind of Mathematical symbol should I use? thanks.
$\tan(A)=\dfrac{\max(|x_2-x_1|,|y_2-y_1|)}{\min(|x_2-x_1|,|y_2-y_1|)}$

Or:

$\tan(A)=\max\left(\dfrac{|x_2-x_1|}{|y_2-y_1|},\dfrac{|y_2-y_1|}{|x_2-x_1|}\right)$

where $\max(a,b)$ equals the greatest of $a$ and $b$
$$\tan(A) = \begin{cases}
|y_2 - y_1| \ge |x_2 - x_1| &amp;: \huge{\frac{|y_2 - y_1|}{|x_2 - x_1|}} \\ \\ \\
|y_2 - y_1| \le |x_2 - x_1| &amp;: \huge{\frac{|x_2 - x_1|}{|y_2 - y_1|}} \\
\end{cases}$$