Re: ncdigest V1 #392 (Coordinate Variables)

Chuck Denham (
Wed, 4 Jun 1997 11:09:22 -0400

        The discussion about "coordinate variables" reminds us here in
Massachusetts of a recent scandal over questionable expenditures by our
state treasurer.  He assured our citizens that it was okay for him and his
cornies to continue scamming the public so blatantly, because they had
always done so.
        Our theory on "coordinate variables" relies heavily on the
universally trusted "if-it-walks-like-a-duck" rationale.
        We use multi-dimensional "coordinate variables" -- admittedly in
technical violation of the NetCDF rules -- because they are so intuitive
and useful.  It is no trouble to test for a variable whose dimension names
also happen to be the names of variables (and vice-versa) -- that's what we
have always assumed by the term "coordinate variable".  The "ncvar/iscoord"
method in our "NetCDF Toolbox for Matlab
<> invokes that idea.
        Rather than adopt a scheme involving extra attributes that may have
to be parsed, we would prefer that the official definition of "coordinate
variable" be expanded to incorporate multiple "coordinate dimensions".

Dr. Charles R. Denham       e-mail:,
U.S. Geological Survey      WWW:
384 Woods Hole Road         voice:  (508) 457-2318
Woods Hole, MA 02543-1598   fax:    (508) 457-2310

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