<h3>xmin function</h3>
Returns the minimum x coordinate of a geometry. Calculations are in the Spatial Reference System of this Geometry. 

<h4>Syntax</h4>
<pre>xmin(geom)</pre>

<h4>Arguments</h4>
geom &rarr; a geometry

<h4>Example</h4>
<pre> xmin($geometry) &rarr; returns minimum x coordinate of $geometry</pre>

