# UnSegment

This operator is the inverse to any segmentation operator. While a segmentation operator segments its input concept's `ColumnSet` into several `ColumnSet`s, UnSegment joins several `ColumnSet`s into one. This operator makes sense only if a segmentation operator was applied previously in the chain, because it exactly reverses the function of that operator. To do so, the parameter UnsegmentAttribute specifies indirectly which of the three segmentation operators is reversed:

If a SegmentationStratified operator is reversed, this parameter gives the name of the `BaseAttribute` that was used for stratified segmentation. Note that this `BaseAttribute` must belong to TheOutputConcept of this operator, because the re-unified `ColumnSet` contains different values for this attribute (whereas before the execution of this operator, the different `ColumnSet`s did not contain this attribute, but each represented one of its values).

If a SegmentationByPartitioning operator is reversed, this parameter must have the value "(Random)".

If a SegmentationWithKMean operator is reversed, this parameter must have the value "(KMeans)".

Note that the segmentation to be reversed by this operator can be any segmentation in the chain before this operator.

ParameterName | ObjectType | Type | Remarks
TheInputConcept | CON | IN | inherited
UnsegmentAttribute | BA | OUT | see text
TheOutputConcept | CON | OUT | inherited