/// <summary>
 /// MDX 'NonEmpty' function. Returns the set of tuples that are not empty from a specified set, based on the cross product of the specified set with a second set.
 /// </summary>
 /// <param name="set1">A valid Multidimensional Expressions (MDX) expression that returns a set.</param>
 /// <param name="set2">A valid Multidimensional Expressions (MDX) expression that returns a set.</param>
 /// <returns></returns>
 public static Set NonEmpty(ICubeObject set1, ICubeObject set2)
 {
     if (set2 == null)
     {
         return(new Set($"NonEmpty({set1})"));
     }
     return(new Set($"NonEmpty({set1}, {set2})"));
 }
 /// <summary>
 /// MDX 'IsEmpty' function. Returns whether the evaluated expression is the empty cell value.
 /// </summary>
 /// <param name="obj"></param>
 /// <returns></returns>
 public static bool IsEmpty(ICubeObject obj) => new Member($"IsEmpty({obj})");