NX User Defined Feature (UDF) expressions multiply when edited

UDF expressions multiply when edited

This behavior is designed as intended. The UDF contained Pattern Features type Variational, and therefore the number of expressions can drastically grow due to an edit. Per development, Pattern Method ‘variational’ is designed to be the most comprehensive, and the most inefficient method of making copies of input feature’s geometry.  A majority of user workflows do not need to use the variational method.  Each instance creates a fully-fledged feature with a full copy of the selected input features.  Also, each expression of the input feature is copied regardless of whether the expression will have a different value.   

Pattern Method ‘simple’ provides a halfway compromise between making copies of the geometry (using Pattern Geometry) and creating a fully-fledged associative feature at each instance location.  Expression copies are created only for the instance which are not identical to the Pattern Feature’s input feature.