question about sublist



Hello,
  I have a large list of floating point numbers.

Does anyone have a clever predicate to sublist which will extract the
  elements whose immediate successors have the same sign?

I can do it by creating a new list whose elements are pairs of
successive elements of the first list, but that seems to waste a lot
of storage.

Any suggestions will be welcome.

TIA,
  -sen


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  | Sheldon E. Newhouse            |    e-mail: sen1 at math.msu.edu           |
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