dist(x1, y1, x2, y2)
Calculates the distance between two points.
Type: function
Parameter(s):
- x1 {Number}:The x-coordinate of the first point. 
- y1 {Number}:The y-coordinate of the first point. 
- x2 {Number}:The x-coordinate of the second point. 
- y2 {Number}:The y-coordinate of the second point. 
Returns:
- 
    {Number}:
 The distance.