Data Step Programming (from Fraktal SAS Programming)

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What is this?

The triplex name "Data Step Programming" needs to be explained step-by-step:

  • DATA is the SAS technical term for values operated on.
  • STEP is the SAS conceptual name for a segment-wise oriented coding structure.
  • PROGRAMMING is the SAS term for coding a scripted (not compiled) algorithm.

Data Step Programming is done using the "Data Step Language" (DSL). The Data Step Language is a fully equipped 3rd generation language, modelled on IBM Corporation's PL/1 called successor candidate for FORTRAN.

The Data Step

Simply speaking, SAS processes one "observation" at a time. An observation is a data line, know as "row" to the rDBMS specialist or SQL programmer that is derived from the punch card concept in pioneering ages of IT.

The observation is processed in a one-line-register called "Program Data Vector" (PDV).

Generally speaking, each line of code in DSL applies some function to the PDV, whose content is then written to the dataset generated, either implicitly or on explicitly stated order with an "OUTPUT" statement.

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