At 14:09 31/10/00 -0600, Greg Woolridge wrote:

>Karsten, >I have to disagree with you. On page 455 of the "SAS Language and >Procedures Usage" manual it states "_N_ is an automatic variable whose >value is the number of times the SAS System has begun executing the DATA >step (1, 2, 3, and so on)." If it were the number of times that it passes >the implied return it would be equal to 0 (or missing) for the first >execution.

This seems to be a bit of a nitpicking disagreement to me. When Karsten wrote "_N_ counts the number of traversals past this implied RETURN." all he omitted to do in order to describe the situation correctly was to point out that _N_ is initialised as 1, not 0 (or missing) at the start of the very first iteration of the DATA step.

Beyond that, it is academic to argue as to whether the incrementing of _N_ occurs on executing an (implicit or explicit) RETURN or the start of the next iteration ... since the latter is an inevitable consequence of the former, and there is no way of examining the value of _N_ in between the two!

That's how I see it, anyway!

Kind Regards,

John

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