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MOVE Statement

MOVE stage1 (BEFORE AFTER) stage2 ;

The MOVE statement is used to change the order of the stages. After all data in input data sets have been read, PROC DTREE determines the order (from left to right) of all stages specified in the STAGEIN= data set and display the order in the SAS log. The ordering is determined based on the rule that if stage A is the successor of an outcome of stage B, then stage A should occur to the right of stage B. The MOVE statement can be used to change the order. If the keyword BEFORE is used, stage1 becomes the new successor for all immediate predecessors of stage2, and stage2 becomes the new successor for all outcomes of stage1. An outcome is said to be an immediate predecessor of a stage if the stage is the successor of that outcome. Similarly, if the keyword AFTER is used, the old leftmost (in previous order) successor of outcomes for stage2 becomes the new successor for all outcomes of stage1 and the new successor of all outcomes of stage2 is stage1.

There are two limitations: the END stage cannot be moved, and no stage can be moved after the END stage. In practice, any stage after the END stage is useless.