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Transforming/expanding a list

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  • Subject: [mg127970] Transforming/expanding a list
  • From: Mark Coleman <markspcoleman at>
  • Date: Thu, 6 Sep 2012 04:14:14 -0400 (EDT)
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I'm working on some Mathematica code that will help transform a large set of lists drawn from my company's legacy database systems. A typical row of the raw data looks like


The lists are sequences of real numbers, separating some some number of Strings which for convenicence sake we call "NULL" (as opposed to a proper Mathematica Null). The goal is to create a new list where each NULL is replaced by the real number that most recently proceeds it (note that any number of NULLs may occur before or after any real values). I would like the code to return




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