Syntax

   @XValue([(<x-value>|<list attribute>)][, Reset]) 
   
Arguments

   <x-value>   
   
      The value of the x coordinate stored in the feature.
      
      Range: Real Number   
   
   <list attribute>  
   
      The name of a list attribute that contains coordinates to be stored in the feature.
   
      Range: attribute name containing {} exactly once.  
   
Description

   This function may be used as either a feature function or an attribute value 
   function. When used as a feature function, the optional x-value parameter 
   must be specified. In this case, the @XValue function stores the specified 
   value as the x coordinate of the feature. 
   
   If a list attribute is specified in place of a value, then all the values in 
   that list are supplied as coordinates to the feature; each coordinate is 
   supplied in the same way as a single value.
   
   If the optional Reset parameter is specified, then the coordinates of the 
   feature are cleared before the x value is added. If it is not specified, then 
   the x value is added to the current feature's geometry, either extending a 
   line if the feature was linear or creating a Point-In-Polygon feature out of 
   a polygonal feature.
   
   When used as an attribute value function, the x-value parameter is not 
   specified. In this case, @XValue returns the value of the first x coordinate 
   of the feature. This value is then stored in the attribute.
   
      Warning: @XValue() should generally be used in conjunction with 
      @YValue(). If @XValue() is used on its own, it is possible to create a 
      feature with a different number of X and Y values.